Income Taxes - Schedule of Reconciliation of the Statutory Federal Income Tax Rate to the Company's Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of the Statutory Federal Income Tax Rate to the Company's Effective Tax Rate
Statutory Federal Income Tax Rate	21.00%	21.00%	21.00%
Increase (Decrease) in Income Tax Rate Resulting From:
State Taxes, Net of Federal Income Tax	0.81%	2.53%	2.29%
Tax Reserve Adjustments	0.07%	(0.03%)	0.00%
Low-Income Housing Investments- Federal	0.82%	0.60%	0.22%
Investment Tax Credits- Federal	(1.24%)	(0.84%)	(1.04%)
Bank-Owned Life Insurance	(0.82%)	(0.51%)	(0.55%)
Tax-Exempt Income	(0.50%)	(0.53%)	(1.29%)
Excess Tax Benefits - Stock Compensation	(0.07%)	(0.22%)	(0.34%)
Leveraged Lease	(0.56%)	(1.54%)	(0.83%)
Tax Reform Effects	0.00%	0.00%	(0.75%)
Other	(0.83%)	0.50%	0.02%
Effective Tax Rate	18.68%	20.96%	18.73%

Effective Income Tax Rate Reconciliation, Bank Owned Life Insurance, Percent

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to rents and other costs from leveraged leases under enacted tax laws.

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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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-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 income tax rates.

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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 expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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