Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Tax effect on unrealized gains (losses) recognized on securities available for sale	$ 80	$ 6,394	$ 2,940
Reclassification adjustment on securities available for sale	3,462	5,576	486
Tax effect on net unrealized gains (losses) recognized on securities available for sale	3,542	818	2,454
Tax effect of unrealized gains (losses) recognized on foreign currency forward contracts	760	1,721	1,396
Reclassification adjustment on foreign currency forward contracts	500	533	3,360
Tax effect of net unrealized gains (losses) recognized on foreign currency forward contracts	$ 260	$ 1,187	$ 4,756

Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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