Commitments and Contingencies (Guarantees Outstanding) (Details) - Loans Sold or Securitized With Recourse - Loans Sold or Securitized with Recourse - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Guarantor obligation, maximum potential future payment [Abstract]
Expire in One Year or Less	$ 48
Expire After One Year Through Three Years	533
Expire After Three Years Through Five Years	95
Expire After Five Years	22,836
Total	23,512	$ 26,198
Carrying Value	32,213	37,145
Single Family Residential
Guarantor obligation, maximum potential future payment [Abstract]
Expire in One Year or Less	48
Expire After One Year Through Three Years	341
Expire After Three Years Through Five Years	95
Expire After Five Years	7,840
Total	8,324	10,526
Carrying Value	8,324	10,526
Multifamily residential
Guarantor obligation, maximum potential future payment [Abstract]
Expire in One Year or Less	0
Expire After One Year Through Three Years	192
Expire After Three Years Through Five Years	0
Expire After Five Years	14,996
Total	15,188	15,672
Carrying Value	$ 23,889	$ 26,619