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Consolidated Statements of Cash Flows - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
CASH FLOWS PROVIDED BY OPERATING ACTIVITIES: |  |  |
Net income | $ 90,284,000 | $ 33,464,000 | $ 35,745,000
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation | 85,120,000 | 82,445,000 | 75,323,000
Deferred income taxes | (47,228,000) | 13,490,000 | 14,720,000
Tax benefits from share-based payment arrangement exercises |  | 46,000 | 373,000
Share-based payment arrangement compensation expense | 1,250,000 | 883,000 | 1,404,000
Distribution from affiliate | 400,000 |  |
Equity in loss from affiliate | 271,000 | 1,018,000 | 296,000
Changes in other current operating items: |  |  |
Receivables | (5,974,000) | 8,518,000 | 7,968,000
Prepaid expenses and other | (503,000) | (1,173,000) | (1,274,000)
Accounts payable | 11,000 | 594,000 | (4,853,000)
Insurance and claims accruals | 6,737,000 | 3,205,000 | 2,237,000
Accrued liabilities | (2,990,000) | 1,813,000 | 6,419,000
Net cash provided by operating activities | 121,879,000 | 133,801,000 | 128,670,000
CASH FLOWS USED FOR INVESTING ACTIVITIES: |  |  |
Other | (43,000) | (42,000) | (39,000)
Net cash used for investing activities | (95,318,000) | (97,290,000) | (125,081,000)
CASH FLOWS USED FOR FINANCING ACTIVITIES: |  |  |
Borrowings under credit facility and long-term debt | 40,831,000 | 179,687,000 | 141,908,000
Repayment of borrowings under credit facility and long-term debt | (48,717,000) | (209,668,000) | (128,414,000)
Repurchase and retirement of common stock |  | (7,513,000) | (16,175,000)
Dividends on common stock | (4,361,000) | (3,252,000) | (3,342,000)
Issuance of common stock from share-based payment arrangement exercises | 1,090,000 | 4,416,000 | 3,490,000
Change in checks issued in excess of cash balances |  |  | (745,000)
Employee taxes paid in exchange for shares withheld | (47,000) | (127,000) |
Cash in lieu of fractional shares from stock split | (54,000) |  |
Net cash used for financing activities | (11,258,000) | (36,457,000) | (3,278,000)
NET CHANGE IN CASH AND CASH EQUIVALENTS | 15,303,000 | 54,000 | 311,000
CASH AND CASH EQUIVALENTS: |  |  |
Beginning of year | 488,000 | 434,000 | 123,000
End of year | 15,791,000 | 488,000 | 434,000
SUPPLEMENTAL NON-CASH DISCLOSURE: |  |  |
Change in property and equipment not yet paid | (1,559,000) | 4,511,000 | 2,853,000
Income taxes | 14,355,000 | 31,000 | 2,121,000
Interest | 151,000 | 214,000 | 252,000
Revenue Equipment [Member] |  |  |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Gain on disposition of assets | (5,499,000) | (10,502,000) | (5,584,000)
CASH FLOWS USED FOR INVESTING ACTIVITIES: |  |  |
Revenue equipment additions | (148,856,000) | (154,984,000) | (174,165,000)
Proceeds from revenue equipment dispositions | 61,227,000 | 65,082,000 | 56,011,000
Facility [Member] |  |  |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Gain on disposition of assets |  |  | (4,104,000)
Buildings And Land Office Equipment And Other [Member] |  |  |
CASH FLOWS USED FOR INVESTING ACTIVITIES: |  |  |
Revenue equipment additions | (7,693,000) | (7,369,000) | (13,482,000)
Proceeds from revenue equipment dispositions | $ 47,000 | $ 23,000 | $ 6,594,000

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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 25 -Paragraph 19A -URI http://asc.fasb.org/extlink&oid=96949009&loc=SL79513924-113897 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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- Definition Amount of cash inflow from issuance of shares under share-based compensation arrangement. Issuance includes, but is not limited to, exercise of stock options and similar instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901 + Details
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- Definition The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 + Details
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- Definition The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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- Definition The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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