Off-Balance-Sheet Arrangements, Commitments and Contingencies Narrative (Details)	1 Months Ended		3 Months Ended		6 Months Ended
	Jan. 31, 2021 USD ($) contract	May 31, 2020 USD ($) contract	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities			$ 0	$ 7,800,000	$ 1,100,000	$ 8,000,000.0
Lessee, Operating Lease, Number of Contracts | contract	1	1
Operating lease ROU assets			15,472,000		15,472,000		$ 15,063,000
Unsettled trades to purchase securities			41,888,000	26,359,000	41,888,000	26,359,000	0
Unsettled trades to sell securities			0	$ 2,923,000	0	$ 2,923,000	0
Unsettled Issuances of Brokered CDs			$ 0		$ 0		$ 0
Operating lease
Lessee, Lease, Description [Line Items]
Operating lease ROU assets	$ 1,100,000	$ 6,600,000