Commitments and Contingencies - Allowance for Credit Losses for Unfunded Loan Commitments (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2019
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	$ 4,303	$ 4,467	$ 6,077	$ 3,112	$ 4,467	$ 3,112
Provision for credit losses	555		927		391	2,543
Balance at end of period	4,858	$ 4,303	7,004	$ 6,077	4,858	7,004	$ 3,112
Accounting Standards Update [Extensible List]		ASU No. 2016-13		ASU No. 2016-13			ASU No. 2016-13
Impact of new accounting standard
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	0	$ 0	0	$ 1,349	0	1,349
Balance at end of period		0		0			$ 1,349
Balance after adoption of ASU 2016-13
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	$ 4,303	4,467	$ 6,077	4,461	$ 4,467	$ 4,461
Balance at end of period		$ 4,303		$ 6,077			$ 4,461