Commitments, Contingencies and Related Party Transactions (Guarantees Outstanding) (Details) - Loans sold or securitized with recourse - Loans Sold or Securitized with Recourse - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Single Family Residential and Multi-Family Residential with recourse
Guarantees
Maximum potential future payments	$ 33,758	$ 38,722
Carrying value of loans sold or securitized	86,674	113,717
Single Family Residential with recourse
Guarantees
Maximum potential future payments	16,700	20,240
Carrying value of loans sold or securitized	16,700	20,240
Multifamily Residential with recourse
Guarantees
Maximum potential future payments	17,058	18,482
Carrying value of loans sold or securitized	$ 69,974	$ 93,477