Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 37,297	$ 30,214	$ 73,542	$ 63,979
Unrealized gains (losses) on securities:
Change in unrealized holding gains (losses), net	42,273	(45,553)	107,585	(12,877)
Less: Reclassification adjustment for gains included in net income	(2,598)	(967)	(5,531)	(8,303)
Change in unrealized gains (losses) on securities during the period	39,675	(46,520)	102,054	(21,180)
Change in unrealized losses on derivative hedges	(2,894)		(7,034)
Income tax (expense) benefit	(13,954)	17,569	(36,007)	8,033
Other comprehensive income (loss)	22,827	(28,951)	59,013	(13,147)
Comprehensive income	$ 60,124	$ 1,263	$ 132,555	$ 50,832

Change in unrealized holding gains, net of the reclassification adjustment for gains included in net income.

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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.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax, 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), attributable to parent entity.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax 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) allocated to other comprehensive income (loss).

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