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	$ 210,544	$ 181,878	$ 116,377
Other Comprehensive Income (Loss), Net of Tax
Unrealized gains (losses) on available-for-sale securities	77,158	(15,608)	3,428
Reclassification adjustment for (gains) losses included in net income	(14,423)	12	636
Net unrealized gains (losses) on available-for-sale securities	62,735	(15,596)	4,064
Tax effect	(15,896)	3,952	(1,563)
Net of tax amount	46,839	(11,644)	2,501
Unrealized (losses) gains on derivatives used for cash flow hedges	(7,047)	3,286	444
Reclassification adjustment for losses included in net income	10,816	2,334	4,892
Net unrealized gains on derivatives used for cash flow hedges	3,769	5,620	5,336
Tax effect	(955)	(1,424)	(2,083)
Net of tax amount	2,814	4,196	3,253
Total other comprehensive income (loss), net of tax	49,653	(7,448)	5,754
Total Comprehensive Income	$ 260,197	$ 174,430	$ 122,131