Other Assets and Receivables (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Investment in Qualified Affordable Housing Limited Partnerships
Investments for qualified affordable housing limited partnerships	$ 14,900,000	$ 14,900,000
Additional contribution on qualified affordable housing limited partnerships	9,000,000
Amortization expense	1,800,000	2,300,000
Tax credit	2,000,000.0	2,500,000
Other Receivables
Other receivables	11,500,000	5,600,000
Short term receivables	4,600,000	3,100,000
Other receivables, collateral recorded against outstanding hedges	3,900,000	$ 590,000
Other receivables, margins called on forward trades	$ 2,100,000