Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 128,294	$ 264,670	$ 176,100
Other comprehensive income (loss), before tax:
Gains (losses) arising during the period	693	(2,231)	3,111
Amount reclassified from accumulated other comprehensive loss	97	(64)	60
Total gain (loss) on minimum pension liability	790	(2,295)	3,171
Interest rate derivatives:
Gains arising during period	3,539
Amount reclassified from accumulated other comprehensive loss	(1,905)
Total income (loss) from Interest rate derivatives	1,634
Other-than-temporary impairment loss on held-to-maturity securities:
Non-credit loss on other-than-temporary impairment			(6,543)
Amount reclassified from accumulated other comprehensive loss	333	333
Total non-credit loss on other-than-temporary impairment	333	333	(6,543)
Other comprehensive income (loss), before tax	2,757	(1,962)	(3,372)
Income tax (provision) benefit related to items of comprehensive loss	(185)	630	(1,052)
Other comprehensive income (loss), net of tax	2,572	(1,332)	(4,424)
Comprehensive income	130,866	263,338	171,676
Comprehensive loss attributable to noncontrolling interest	18,328
Comprehensive income available to common stockholders	$ 149,194	$ 263,338	$ 171,676