CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other comprehensive income (loss)
Net income	$ 126,487	$ 163,626	$ 160,204
Amounts related to available-for-sale securities:
Change in net unrealized gains	(101,001)	91,750	54,263
Reclassification adjustment for amounts included in net income	0	0	62
Amounts related to cash flow hedges:
Change in net unrealized gains (losses)	9,320	(22,262)	(51,751)
Reclassification adjustment for amounts included in net income	16,914	19,882	28,066
Other comprehensive income (loss)	(74,767)	89,370	30,640
Comprehensive income	$ 51,720	$ 252,996	$ 190,844

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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