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v2.4.1.9

Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Cash flows from operating activities: |  |  |
Net income | $ 98,650 us-gaap_NetIncomeLoss | $ 86,785 us-gaap_NetIncomeLoss | $ 103,034 us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation | 176,984 us-gaap_Depreciation | 173,019 us-gaap_Depreciation | 166,957 us-gaap_Depreciation
Deferred income taxes | 5,038 us-gaap_DeferredIncomeTaxExpenseBenefit | (8,389)us-gaap_DeferredIncomeTaxExpenseBenefit | (9,068)us-gaap_DeferredIncomeTaxExpenseBenefit
Gain on disposal of property and equipment | (19,260)us-gaap_GainLossOnSaleOfPropertyPlantEquipment | (16,408)us-gaap_GainLossOnSaleOfPropertyPlantEquipment | (20,533)us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Non-cash equity compensation | 6,070 us-gaap_ShareBasedCompensation | 4,809 us-gaap_ShareBasedCompensation | 4,602 us-gaap_ShareBasedCompensation
Insurance and claims accruals, net of current portion | (8,455)wern_IncreaseDecreaseInSelfInsuranceReservesNoncurrent | 6,400 wern_IncreaseDecreaseInSelfInsuranceReservesNoncurrent | 4,250 wern_IncreaseDecreaseInSelfInsuranceReservesNoncurrent
Other | 1,107 us-gaap_OtherOperatingActivitiesCashFlowStatement | (541)us-gaap_OtherOperatingActivitiesCashFlowStatement | (237)us-gaap_OtherOperatingActivitiesCashFlowStatement
Changes in certain working capital items: |  |  |
Accounts receivable, net | (35,080)us-gaap_IncreaseDecreaseInAccountsReceivable | (20,514)us-gaap_IncreaseDecreaseInAccountsReceivable | 7,579 us-gaap_IncreaseDecreaseInAccountsReceivable
Other current assets | (25,926)us-gaap_IncreaseDecreaseInOtherCurrentAssets | 3,398 us-gaap_IncreaseDecreaseInOtherCurrentAssets | 17,581 us-gaap_IncreaseDecreaseInOtherCurrentAssets
Accounts payable | (1,497)us-gaap_IncreaseDecreaseInAccountsPayableTrade | 2,793 us-gaap_IncreaseDecreaseInAccountsPayableTrade | (20,172)us-gaap_IncreaseDecreaseInAccountsPayableTrade
Other current liabilities | 8,934 us-gaap_IncreaseDecreaseInOtherCurrentLiabilities | 1,105 us-gaap_IncreaseDecreaseInOtherCurrentLiabilities | 1,103 us-gaap_IncreaseDecreaseInOtherCurrentLiabilities
Net cash provided by operating activities | 206,565 us-gaap_NetCashProvidedByUsedInOperatingActivities | 232,457 us-gaap_NetCashProvidedByUsedInOperatingActivities | 255,096 us-gaap_NetCashProvidedByUsedInOperatingActivities
Cash flows from investing activities: |  |  |
Additions to property and equipment | (296,649)us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | (211,329)us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | (284,942)us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Retirements of property and equipment | 84,355 us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment | 59,413 us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment | 60,015 us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment
Decrease in notes receivable | 14,390 us-gaap_ProceedsFromCollectionOfNotesReceivable | 10,679 us-gaap_ProceedsFromCollectionOfNotesReceivable | 8,122 us-gaap_ProceedsFromCollectionOfNotesReceivable
Other | (5,583)us-gaap_PaymentsForProceedsFromOtherInvestingActivities | 979 us-gaap_PaymentsForProceedsFromOtherInvestingActivities | 0 us-gaap_PaymentsForProceedsFromOtherInvestingActivities
Net cash used in investing activities | (203,487)us-gaap_NetCashProvidedByUsedInInvestingActivities | (140,258)us-gaap_NetCashProvidedByUsedInInvestingActivities | (216,805)us-gaap_NetCashProvidedByUsedInInvestingActivities
Cash flows from financing activities: |  |  |
Repayments of short-term debt | (10,000)us-gaap_RepaymentsOfLinesOfCredit | (20,000)us-gaap_RepaymentsOfLinesOfCredit | (160,000)us-gaap_RepaymentsOfLinesOfCredit
Proceeds from issuance of short-term debt | 10,000 us-gaap_ProceedsFromLinesOfCredit | 0 us-gaap_ProceedsFromLinesOfCredit | 180,000 us-gaap_ProceedsFromLinesOfCredit
Repayments of long-term debt | (40,000)us-gaap_RepaymentsOfLongTermLinesOfCredit | (40,000)us-gaap_RepaymentsOfLongTermLinesOfCredit | 0 us-gaap_RepaymentsOfLongTermLinesOfCredit
Proceeds from issuance of long-term debt | 75,000 us-gaap_ProceedsFromLongTermLinesOfCredit | 10,000 us-gaap_ProceedsFromLongTermLinesOfCredit | 70,000 us-gaap_ProceedsFromLongTermLinesOfCredit
Change in net checks issued in excess of cash balances | 0 us-gaap_IncreaseDecreaseInBookOverdrafts | 0 us-gaap_IncreaseDecreaseInBookOverdrafts | (6,671)us-gaap_IncreaseDecreaseInBookOverdrafts
Dividends on common stock | (14,440)us-gaap_PaymentsOfDividendsCommonStock | (14,587)us-gaap_PaymentsOfDividendsCommonStock | (124,391)us-gaap_PaymentsOfDividendsCommonStock
Repurchases of common stock | (30,587)us-gaap_PaymentsForRepurchaseOfCommonStock | (20,060)us-gaap_PaymentsForRepurchaseOfCommonStock | 0 us-gaap_PaymentsForRepurchaseOfCommonStock
Tax withholding related to net share settlements of restricted stock awards | (1,977)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation | (1,804)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation | (674)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation
Stock options exercised | 7,012 us-gaap_ProceedsFromStockOptionsExercised | 2,548 us-gaap_ProceedsFromStockOptionsExercised | 6,035 us-gaap_ProceedsFromStockOptionsExercised
Excess tax benefits from equity compensation | 1,324 us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities | 379 us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities | 150 us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities
Net cash used in financing activities | (3,668)us-gaap_NetCashProvidedByUsedInFinancingActivities | (83,524)us-gaap_NetCashProvidedByUsedInFinancingActivities | (35,551)us-gaap_NetCashProvidedByUsedInFinancingActivities
Effect of exchange rate fluctuations on cash | (484)us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents | (425)us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents | 276 us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents
Net increase (decrease) in cash and cash equivalents | (1,074)us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease | 8,250 us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease | 3,016 us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
Cash and cash equivalents, beginning of period | 23,678 us-gaap_CashAndCashEquivalentsAtCarryingValue | 15,428 us-gaap_CashAndCashEquivalentsAtCarryingValue | 12,412 us-gaap_CashAndCashEquivalentsAtCarryingValue
Cash and cash equivalents, end of period | 22,604 us-gaap_CashAndCashEquivalentsAtCarryingValue | 23,678 us-gaap_CashAndCashEquivalentsAtCarryingValue | 15,428 us-gaap_CashAndCashEquivalentsAtCarryingValue
Supplemental disclosures of cash flow information: |  |  |
Interest paid | 820 us-gaap_InterestPaid | 466 us-gaap_InterestPaid | 245 us-gaap_InterestPaid
Income taxes paid | 76,849 us-gaap_IncomeTaxesPaidNet | 66,032 us-gaap_IncomeTaxesPaidNet | 67,968 us-gaap_IncomeTaxesPaidNet
Supplemental schedule of non-cash investing activities: |  |  |
Notes receivable issued upon sale of property and equipment | 14,385 us-gaap_NotesIssued1 | 17,110 us-gaap_NotesIssued1 | 10,564 us-gaap_NotesIssued1
Issuance of notes payable | 6,233 us-gaap_NotesAssumed1 | 0 us-gaap_NotesAssumed1 | 0 us-gaap_NotesAssumed1
Change in fair value of interest rate swap | (1,180)us-gaap_IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments1 | 0 us-gaap_IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments1 | 0 us-gaap_IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstruments1
Property and equipment acquired included in accounts payable | 2,067 us-gaap_CapitalExpendituresIncurredButNotYetPaid | 5,403 us-gaap_CapitalExpendituresIncurredButNotYetPaid | 109 us-gaap_CapitalExpendituresIncurredButNotYetPaid
Property and equipment disposed included in other receivables | $ 0 wern_PropertyAndEquipmentDisposedIncludedInOtherReceivables | $ 434 wern_PropertyAndEquipmentDisposedIncludedInOtherReceivables | $ 311 wern_PropertyAndEquipmentDisposedIncludedInOtherReceivables

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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=6519514 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=6518256 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.19) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.18) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.22) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9 + Details
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- Definition The fair value of notes assumed in noncash investing or financing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition The fair value of notes issued in noncash investing and financing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition The net cash outflow or inflow from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3095-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3098-108585 + Details
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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 -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 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=31042434&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 -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 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=31042434&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 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&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 -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: 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=31042434&loc=d3e3213-108585 + Details
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- Definition The cash inflow associated with principal collections from a borrowing supported by a written promise to pay an obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585 + Details
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- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph f -Article 4 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 4: 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=31042434&loc=d3e3255-108585 + 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 -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: 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=31042434&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 -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: 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=31042434&loc=d3e3179-108585 + Details
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- Definition The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: 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=31042434&loc=d3e3255-108585 + Details
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- Definition Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph f -Article 4 Reference 3: 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=31042434&loc=d3e3291-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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