Effective Income Tax Rate Reconciliation, Tax Exempt Income, Life Insurance, Amount

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Life Insurance, Percent

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Other Than Life Insurance, Amount

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Effective Income Tax Rate Reconciliation, Tax Exempt Income, Other Than Life Insurance, Percent

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Increase (Decrease) in Taxes [Abstract]

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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 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 nondeductible expense for share-based payment arrangement.

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Amount 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 increase (decrease) in the income tax rates.

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Amount of reported income tax expense (benefit) in excess of (less than) 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 award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount 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 state and local income tax expense (benefit).

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INCOME TAXES - Income Tax Expense 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
Amount
Statutory tax expense									$ 19,633	$ 18,433	$ 17,703
Increase (decrease) in taxes from:
Tax rate changes									0	0	(767)
Tax exempt interest									(8,137)	(4,875)	(6,257)
BOLI									(536)	(484)	(613)
Share-based compensation									(70)	(167)	(191)
State business tax									329	217	297
Other, net									117	97	(9)
Income tax expense	$ 4,265	$ 3,783	$ 2,809	$ 479	$ 2,854	$ 3,661	$ 3,569	$ 3,137	$ 11,336	$ 13,221	$ 10,163
Percent of Pre-Tax Income
Statutory tax expense									21.00%	21.00%	21.00%
Increase (Decrease) in Taxes From:
Percent of Pre-tax income, Tax rate changes									0.00%	0.00%	(0.90%)
Percent of Pre-tax income, Tax exempt interest									(8.70%)	(5.50%)	(7.40%)
Percent of Pre-tax income, Bank owned life insurance									(0.60%)	(0.50%)	(0.70%)
Percent of Pre-tax income, Share-based compensation									(0.10%)	(0.20%)	(0.20%)
Percent of Pre-tax income, State business tax									0.40%	0.20%	0.30%
Percent of Pre-tax income, Other net									0.10%	0.10%	0.00%
Percent of Pre-tax income, Income tax expense									12.10%	15.10%	12.10%