Off-Balance-Sheet Arrangements, Commitments and Contingencies Narrative (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) contract	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Leases:
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities	$ 1,100,000	$ 227,000
Lessee, Operating Lease, Number of Contracts | contract	1
Operating lease ROU assets	$ 15,788,000		$ 15,063,000
Securities:
Unsettled trades to purchase securities	23,473,000	14,596,000	0
Unsettled trades to sell securities	0	$ 67,247,000	0
Deposits:
Unsettled Issuances of Brokered CDs	0		0
Operating Leased Assets [Line Items]
Operating lease ROU assets	15,788,000		$ 15,063,000
Operating lease
Leases:
Operating lease ROU assets	1,100,000
Operating Leased Assets [Line Items]
Operating lease ROU assets	$ 1,100,000