Loan Sales and Servicing - Residential MSRs (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance				$ 42,022
Increase (decrease) in fair value:
Ending balance		$ 29,035		29,035
Residential Mortgage
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance		31,232	$ 47,545	42,022	$ 51,539
Additions		2,739	1,646	4,410	2,705
Increase (decrease) in fair value:
Due to changes in valuation inputs or assumptions		(2,674)	(4,691)	(12,814)	(7,034)
Due to other changes in fair value	[1]	(2,262)	(2,534)	(4,583)	(5,244)
Ending balance		$ 29,035	$ 41,966	$ 29,035	$ 41,966

[1] Represents the realization of expected net servicing cash flows, expected borrower repayments and the passage of time.