Mortgage Banking Activities Mortgage Banking Activities, Mortgage Banking Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Mortgage Banking Revenue [Abstract]
Net realized gains on sale of mortgage loans	$ 20,783	$ 24,109	$ 46,783	$ 33,826
Net change in unrealized gain (loss) on mortgage loans held for sale	1,783	5,024	(5,172)	8,585
Net change in the fair value of mortgage loan commitments	(1,253)	3,381	(10,233)	22,398
Net change in the fair value of forward sales contracts	(11,309)	6,671	3,913	(4,054)
Total production revenue	10,004	39,185	35,291	60,755
Servicing revenue	11,215	14,751	23,041	30,348
Total mortgage banking revenue	$ 21,219	$ 53,936	$ 58,332	$ 91,103