Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Reserve for unfunded lending commitments	$ 32,559	$ 29,907	$ 48,992	$ 3,974