Fair Value Measurements - Roll Forward, Level 3 (Details) - Level 3 - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Rollforward for financial instruments measured at fair value using Level 3 inputs
Asset balance, beginning of period	$ 109,887	$ 119,893	$ 122,699	$ 116,566
Purchases/Additions	93,779	16,600	112,538	33,888
Sales/Reductions	(26,768)	(11,108)	(49,593)	(18,084)
Transfers into Level 3	2,746	(612)	8,967	425
Total gains or losses (realized or unrealized):
Included in Net Income	(6,444)	(14,279)	(21,411)	(22,301)
Asset balance, end of period	173,200	110,494	173,200	110,494
Loans Held for Sale
Rollforward for financial instruments measured at fair value using Level 3 inputs
Asset balance, beginning of period	79,588	57,844	67,195	50,464
Purchases/Additions	34,339	14,053	48,623	29,480
Sales/Reductions	(26,768)	(11,108)	(30,943)	(18,084)
Transfers into Level 3	2,746	(612)	8,967	425
Total gains or losses (realized or unrealized):
Included in Net Income	2,031	(3,378)	(1,906)	(5,486)
Asset balance, end of period	91,936	56,799	91,936	56,799
MSR
Rollforward for financial instruments measured at fair value using Level 3 inputs
Asset balance, beginning of period	30,299	62,049	55,504	66,102
Purchases/Additions	59,440	2,547	63,915	4,408
Sales/Reductions			(18,650)
Total gains or losses (realized or unrealized):
Included in Net Income	(8,475)	(10,901)	(19,505)	(16,815)
Asset balance, end of period	$ 81,264	$ 53,695	$ 81,264	$ 53,695