Mortgage Banking Activities Mortgage Banking Activities, Mortgage Banking Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Mortgage Banking Revenue [Abstract]
Net realized gains on sale of mortgage loans	$ 8,971	$ 9,063	$ 24,838	$ 28,699
Net change in unrealized gain on mortgage loans held for sale	97	(2,135)	965	(2,457)
Net change in the fair value of mortgage loan commitments	514	(2,446)	4,733	(1,496)
Net change in the fair value of forward sales contracts	4,232	2,768	3,015	1,871
Total production revenue	13,814	7,250	33,551	26,617
Servicing revenue	16,366	16,286	48,594	49,290
Total mortgage banking revenue	$ 30,180	$ 23,536	$ 82,145	$ 75,907