Income Taxes Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory tax rate	21.00%	21.00%	21.00%
Tax credit investments	(5.70%)	(4.60%)	(6.10%)
Tax-exempt income	(4.90%)	(3.90%)	(4.10%)
Bank owned life insurance	(0.70%)	(0.40%)	(0.40%)
State income taxes, net of federal benefit	1.10%	0.20%	2.00%
Change in valuation allowance	0.00%	1.80%	(0.10%)
Re-measurement of net DTA due to the Tax Act	0.00%	0.00%	(0.30%)
Executive compensation	0.00%	0.00%	0.10%
FDIC Premium	0.30%	0.00%	0.00%
Penalties	0.20%	0.00%	0.00%
Other, net	0.70%	0.20%	(1.60%)
Effective income tax rate	12.00%	14.30%	10.50%

Effective Income Tax Rate Reconciliation Bank Owned Life Insurance

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Effective Income Tax Rate Reconciliation, FDIC Premium, Percent

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Effective Income Tax Rate Reconciliation Low Income Housing Investments

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Effective Income Tax Rate Reconciliation, Penalties, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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