Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Other Comprehensive Income [Abstract]
Tax effect on unrealized gains (losses) recognized on securities available for sale	$ 2,940	$ 133	$ 6,345
Reclassification adjustment on securities available for sale	486	7,155	5,656
Tax effect on net unrealized gains (losses) on securities available for sale	2,454	7,288	689
Tax effect of unrealized gains (losses) recognized on foreign currency forward contracts	1,396	3,647	1,268
Reclassification adjustment on foreign currency forward contracts	3,360	1,268	304
Tax effect of net unrealized gains (losses) recognized on foreign currency forward contracts	4,756	4,915	964
Tax effect of net unrealized gains (losses) recognized on pension benefit obligation	$ 0	$ 0	$ 0

Tax effect of the appreciation (loss) in the value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) losses.

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Tax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Tax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).

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Tax effect of the income statement impact of the reclassification adjustment for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Tax effect of the income statement impact of the reclassification adjustment of accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges realized in net income. Also includes reclassification adjustments of an entity's share of an equity investee's deferred hedging gain (loss) realized in net income.

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Tax effect of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

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