101 - Document - Document and Entity Information link:calculationLink link:presentationLink link:definitionLink 103 - Statement - Consolidated Balance Sheets link:calculationLink link:presentationLink link:definitionLink 104 - Statement - Consolidated Balance Sheets (Parenthetical) link:calculationLink link:presentationLink link:definitionLink 105 - Statement - Consolidated Statements of Income link:calculationLink link:presentationLink link:definitionLink 106 - Statement - Consolidated Statements of Comprehensive Income link:calculationLink link:presentationLink link:definitionLink 107 - Statement - Consolidated Statements of Cash Flows link:calculationLink link:presentationLink link:definitionLink 108 - Disclosure - Nature of Business link:calculationLink link:presentationLink link:definitionLink 109 - Disclosure - Basis of Presentation link:calculationLink link:presentationLink link:definitionLink 110 - Disclosure - Net Income Per Common Share link:calculationLink link:presentationLink link:definitionLink 111 - Disclosure - Acquisitions link:calculationLink link:presentationLink link:definitionLink 112 - Disclosure - Fair Value of Financial Instruments link:calculationLink link:presentationLink link:definitionLink 113 - Disclosure - Auction Rate Securities link:calculationLink link:presentationLink link:definitionLink 114 - Disclosure - Insurance link:calculationLink link:presentationLink link:definitionLink 115 - Disclosure - Line of Credit link:calculationLink link:presentationLink link:definitionLink 116 - Disclosure - Benefit Plans link:calculationLink link:presentationLink link:definitionLink 117 - Disclosure - Commitments and Contingencies link:calculationLink link:presentationLink link:definitionLink 118 - Disclosure - Income Taxes link:calculationLink link:presentationLink link:definitionLink 119 - Disclosure - Segment Information link:calculationLink link:presentationLink link:definitionLink 120 - Disclosure - Basis of Presentation (Tables) link:calculationLink link:presentationLink link:definitionLink 121 - Disclosure - Net Income Per Common Share (Tables) link:calculationLink link:presentationLink link:definitionLink 122 - Disclosure - Acquisitions (Tables) link:calculationLink link:presentationLink link:definitionLink 123 - Disclosure - Fair Value of Financial Instruments (Tables) link:calculationLink link:presentationLink link:definitionLink 124 - Disclosure - Auction Rate Securities (Tables) link:calculationLink link:presentationLink link:definitionLink 125 - Disclosure - Insurance (Tables) link:calculationLink link:presentationLink link:definitionLink 126 - Disclosure - Line of Credit (Tables) link:calculationLink link:presentationLink link:definitionLink 127 - Disclosure - Benefit Plans (Tables) link:calculationLink link:presentationLink link:definitionLink 128 - Disclosure - Segment Information (Tables) link:calculationLink link:presentationLink link:definitionLink 129 - Disclosure - Basis of Presentation - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 130 - Disclosure - Segments and Their Activities (Detail) link:calculationLink link:presentationLink link:definitionLink 131 - Disclosure - Calculations of Basic and Diluted Net Income Per Common Share (Detail) link:calculationLink link:presentationLink link:definitionLink 132 - Disclosure - Antidilutive Shares Excluded from Calculation of Net Income Per Common Share (Detail) link:calculationLink link:presentationLink link:definitionLink 133 - Disclosure - Acquisitions - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 134 - Disclosure - Preliminary Purchase Price and Related Allocations (Detail) link:calculationLink link:presentationLink link:definitionLink 135 - Disclosure - Fair Value of Financial Instruments (Detail) link:calculationLink link:presentationLink link:definitionLink 136 - Disclosure - Fair Value of Financial Instruments (Parenthetical) (Detail) link:calculationLink link:presentationLink link:definitionLink 137 - Disclosure - Auction Rate Securities - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 138 - Disclosure - Significant Assumptions Used to Determine Fair Value of Auction Rate Securities (Detail) link:calculationLink link:presentationLink link:definitionLink 139 - Disclosure - Changes in Cost Basis and Fair Value of Auction Rate Securities (Detail) link:calculationLink link:presentationLink link:definitionLink 140 - Disclosure - Insurance - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 141 - Disclosure - Standby Letters of Credit, Surety Bonds and Restricted Insurance Deposits Outstanding to Collaterize Self-Insurance Obligations (Detail) link:calculationLink link:presentationLink link:definitionLink 142 - Disclosure - Line of Credit - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 143 - Disclosure - Company's Interest Rate Swap Contracts on Consolidated Financial Statements (Detail) link:calculationLink link:presentationLink link:definitionLink 144 - Disclosure - Components of Net Periodic Benefit Cost of Defined Benefit Plans and Post-Retirement Benefit Plans (Detail) link:calculationLink link:presentationLink link:definitionLink 145 - Disclosure - Commitments and Contingencies - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 146 - Disclosure - Income Taxes - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 147 - Disclosure - Segment Information - Additional Information (Detail) link:calculationLink link:presentationLink link:definitionLink 148 - Disclosure - Reportable Operating Segments (Detail) link:calculationLink link:presentationLink link:definitionLink