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Fair Value Measurements - Schedule of Reconciliation of Level 3 Investments Available-for-Sale Securities (Detail) (USD $)
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3 Months Ended |
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Mar. 31, 2015
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| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | |
| Balance, beginning of period | $ 27,273,000us-gaap_AvailableForSaleSecurities |
| Transfers to / purchases of available-for-sale debt securities. | 5,000,000us-gaap_PaymentsToAcquireAvailableForSaleSecurities |
| Balance, end of period | 22,809,000us-gaap_AvailableForSaleSecurities |
| Level 3 [Member] | |
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | |
| Balance, beginning of period |
27,300,000us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Transfers to / purchases of available-for-sale debt securities. |
5,000,000us-gaap_PaymentsToAcquireAvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Payments on available-for-sale debt securities |
(7,600,000)us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Sale of available-for-sale debt securities |
(2,300,000)us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Gains on debt securities recorded in earnings. |
300,000us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNet / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Gains on debt securities recorded in OCI |
100,000us-gaap_AvailableForSaleSecuritiesChangeInNetUnrealizedHoldingGainLoss / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
| Balance, end of period |
$ 22,800,000us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
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- Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The cash outflow to acquire debt and equity securities not classified as either held-to-maturity securities or trading securities which would be classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The cash outflow to acquire debt securities classified as available-for-sale securities, because they are not classified as either held-to-maturity securities or trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The cash inflow associated with the sale of debt securities classified as available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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