v2.4.1.9

Share Repurchases - Additional information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified | 3 Months Ended | 1 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2015 | Apr. 30, 2015 | Nov. 04, 2010 | Apr. 14, 2015
Accelerated Share Repurchases [Line Items] |  |  |  |
Purchase of treasury stock (in shares) | 891 us-gaap_TreasuryStockSharesAcquired |  |  |
Purchase of treasury stock | $ 70,063 us-gaap_TreasuryStockValueAcquiredCostMethod |  |  |
Purchase of treasury stock, average price per share | $ 78.60 us-gaap_TreasuryStockAcquiredAverageCostPerShare |  |  |
Share repurchase program, authorized amount |  |  | 274,056 us-gaap_StockRepurchaseProgramAuthorizedAmount1 |
Subsequent Event |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |
Purchase of treasury stock (in shares) |  | 176 us-gaap_TreasuryStockSharesAcquired / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |
Purchase of treasury stock |  | 14,050 us-gaap_TreasuryStockValueAcquiredCostMethod / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |
Purchase of treasury stock, average price per share |  | $ 79.96 us-gaap_TreasuryStockAcquiredAverageCostPerShare / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |
Share repurchase program, authorized amount |  |  |  | 725,944 us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
Share repurchase program, outstanding authorizations available for share repurchase |  |  |  | $ 1,000,000 us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1 / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember

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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
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