Loan Servicing (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Transfers and Servicing of Financial Assets [Abstract]
Serviced sold mortgage loans	$ 1,590,000,000	$ 1,390,000,000	$ 1,590,000,000	$ 1,390,000,000	$ 1,450,000,000
Serviced sold mortgage loans with recourse	2,100,000	2,400,000	2,100,000	2,400,000	2,300,000
Servicing fees included in other service income	1,000,000.0	$ 900,000	1,900,000	$ 1,800,000
Mortgage Loans Sold with Recourse, Reserve	$ 44,000		$ 44,000		$ 25,000