Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Tax reform, provisional income tax expense			$ 10,400,000
Tax reform, change in tax rate, provisional income tax expense			4,500,000
Annual limitation on deferred tax asset	$ 6,800,000
Deferred tax assets, state operating loss carryforwards	11,800,000	$ 9,400,000
Valuation allowance	12,379,000	12,125,000
Tax credits	6,860,000	4,085,000	2,390,000
Investment in low-income housing	6,100,000	6,900,000	7,800,000
Unrecognized tax benefits	657,000	611,000
Unrecognized tax benefits, accrued interest and penalties	69,000	66,000
Capital Loss Carryforward
Operating Loss Carryforwards [Line Items]
Valuation allowance	2,300,000	4,000,000.0
Valuation allowance	(1,900,000)
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	163,700,000	121,100,000
State and Local Jurisdiction | Operating Loss Carryforwards
Operating Loss Carryforwards [Line Items]
Valuation allowance	10,100,000	8,100,000
Solar Energy Tax Credit
Operating Loss Carryforwards [Line Items]
Tax credits	4,000,000.0	2,900,000	449,000
Historic Rehabilitation Credit
Operating Loss Carryforwards [Line Items]
Tax credits	1,800,000	0	713,000
Low-income Housing
Operating Loss Carryforwards [Line Items]
Tax credits	1,100,000	1,200,000	$ 1,200,000
Tax credits, expected utilization, 2020	779,000
Tax credits, expected utilization, 2021	538,000
Tax credits, expected utilization, 2022	538,000
Tax credits, expected utilization, 2023	538,000
Tax credits, expected utilization, 2024	322,000
Tax credits, expected utilization, 2025	86,000
Tax credits, expected utilization, 2026	34,000
FSI
Operating Loss Carryforwards [Line Items]
Deferred tax assets, federal operating loss carryforwards	6,700,000	5,100,000
FSI | Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 31,900,000	$ 24,400,000