Mortgage Banking Activities Mortgage Banking Activities, Mortgage Banking Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Mortgage Banking Revenue [Abstract]
Net realized gains on sale of mortgage loans	$ 10,174	$ 10,718	$ 15,867	$ 19,636
Net change in unrealized gain on mortgage loans held for sale	921	1,047	868	(322)
Net change in the fair value of mortgage loan commitments	1,506	(1,124)	4,219	950
Net change in the fair value of forward sales contracts	(732)	(726)	(1,217)	(897)
Total production revenue	11,869	9,915	19,737	19,367
Servicing revenue	16,262	16,431	32,228	33,004
Total mortgage banking revenue	$ 28,131	$ 26,346	$ 51,965	$ 52,371