CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 108,325	$ 140,820	$ 126,487
Amounts related to available-for-sale securities:
Change in net unrealized gains	(98,202)	27,283	(101,001)
Amounts related to cash flow hedges:
Change in net unrealized gains (losses)	(21,675)	(41,059)	9,320
Reclassification adjustment for amounts included in net income	28,550	22,055	16,914
Other comprehensive income (loss)	(91,327)	8,279	(74,767)
Comprehensive income	$ 16,998	$ 149,099	$ 51,720

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

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

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

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