Effective Income Tax Rate Reconciliation, Increase (Decrease) in Income Taxes [Abstract]

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Income Tax Reconciliation, Bank Owned Life Insurance Income (Expense)

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Income tax reconciliation bank-owned life insurance income (expense), rate

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Income tax reconciliation change in fair value of contingent consideration, rate

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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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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 deduction for dividend.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Amount 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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Income Taxes (Schedule of Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Tax expense at Federal statutory rate									$ 18,724	$ 18,518	$ 18,205
Federal statutory rate									21.00%	21.00%	21.00%
Increase (decrease) in taxes resulting from:
State income tax expense, net of federal tax benefit									$ 1,995	$ 2,417	$ 2,162
State income tax expense, net of federal income tax benefit, rate									2.20%	2.70%	2.50%
Tax-exempt income, net									$ (803)	$ (814)	$ (809)
Tax-exempt income, net, rate									(0.90%)	(0.90%)	(0.90%)
BOLI									$ (523)	$ (494)	$ (461)
BOLI, rate									(0.60%)	(0.60%)	(0.50%)
Investment in low-income housing limited partnership									$ (118)	$ 0	$ 0
Investment in low-income housing limited partnership, rate									(0.10%)	0.00%	0.00%
Federal tax credits									$ (93)	$ (364)	$ (364)
Federal tax credits, rate									(0.10%)	(0.40%)	(0.40%)
Dividends received deduction									$ (28)	$ (36)	$ (45)
Dividends received deduction, rate									0.00%	0.00%	(0.10%)
Change in fair value of contingent consideration									$ 0	$ 0	$ (39)
Change in fair value of contingent consideration, rate									0.00%	0.00%	(0.10%)
Share-based compensation									$ 92	$ (221)	$ (444)
Share-based compensation, rate									0.10%	(0.30%)	(0.50%)
Other									$ 85	$ 55	$ 55
Other, rate									0.10%	0.10%	0.10%
Income tax expense	$ 5,514	$ 5,131	$ 5,547	$ 3,139	$ 4,321	$ 5,236	$ 4,662	$ 4,842	$ 19,331	$ 19,061	$ 18,260
Effective tax rate									21.70%	21.60%	21.10%