Effective Income Tax Rate Reconciliation, Partnership Investments

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Effective Income Tax Rate Reconciliation, Share-based Compensation, Federal, Excess Tax Benefit, Amount

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

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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 valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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INCOME TAXES (Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Computed "expected" tax on net income									$ 20,323	$ 56,228	$ 57,804
Increase (decrease) resulting from:
Tax-exempt interest benefit									(2,624)	(5,804)	(5,504)
State income taxes, net of federal tax benefit									4,310	10,523	11,026
Tax credits									(6,966)	(6,613)	(7,613)
Partnership investments									1,105	(351)	572
Valuation allowance									214	13	(440)
Excess tax expense/(benefit) on stock compensation									107	(113)	(270)
Other									388	1,690	(240)
Total income tax expense	$ (27,324)	$ 13,479	$ 15,384	$ 15,318	$ 13,936	$ 14,118	$ 15,402	$ 12,117	$ 16,857	$ 55,573	$ 55,335
Effective tax rates									17.40%	20.80%	20.10%