Fair Value Measurements - Roll Forward, Level 3 (Details) - Level 3 - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Rollforward for financial instruments measured at fair value using Level 3 inputs
Asset balance, beginning of period	$ 122,699	$ 116,566
Purchases/Additions	18,760	17,288
Sales/Reductions	(22,825)	(6,976)
Transfers into Level 3	6,220	1,037
Total gains or losses (realized or unrealized):
Included in Net Income	(14,967)	(8,022)
Asset balance, end of period	109,887	119,893
Loans Held for Sale
Rollforward for financial instruments measured at fair value using Level 3 inputs
Asset balance, beginning of period	67,195	50,464
Purchases/Additions	14,285	15,427
Sales/Reductions	(4,175)	(6,976)
Transfers into Level 3	6,220	1,037
Total gains or losses (realized or unrealized):
Included in Net Income	(3,937)	(2,108)
Asset balance, end of period	79,588	57,844
MSR
Rollforward for financial instruments measured at fair value using Level 3 inputs
Asset balance, beginning of period	55,504	66,102
Purchases/Additions	4,475	1,861
Sales/Reductions	(18,650)
Total gains or losses (realized or unrealized):
Included in Net Income	(11,030)	(5,914)
Asset balance, end of period	$ 30,299	$ 62,049