CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income	$ 93,229	$ 21,297	$ 392,287
Available-for-sale debt securities on which an other-than-temporary impairment has been recognized:
Unrealized gain (loss) on debt securities on which an other-than-temporary impairment has been recognized	550	(16,841)	1,781
Reclassification Adjustement For Other Than Temporary Impairment On Debt Securrities Included In Net Income	6,687	16,517	388
All other unrealized gains and losses on available-for-sale securities:
All other unrealized holding (losses) gains arising during the year	(7,774)	(9,074)	58,478
Reclassification adjustments for net gain included in net income	(6,104)	0	(262)
Other comprehensive (loss) income for the year	(6,641)	(9,398)	60,385
Total comprehensive income	$ 86,588	$ 11,899	$ 452,672