Certain Transfers of Financial Assets Certain Transfers of Financial Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Outstanding balance:
Beginning balance	$ 2,568,362	$ 1,949,785
Loans purchased and originated	4,931,981	4,172,519
Payments and loans sold	(7,052,942)	(5,071,502)
Ending balance	447,401	1,050,802
Fair value adjustment:
Fair value over (under) outstanding balance	8,772	19,689
Increase/(decrease) to fair value	(1,592)	(12,905)
Fair value over (under) outstanding balance	7,180	6,784
Loans held for sale	454,581	1,057,586	$ 2,577,134
Small Business Administration Loans [Member]
Fair value adjustment:
Fair value over (under) outstanding balance	$ 5,800	299
Fair value over (under) outstanding balance		$ 1,100