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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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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 operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Accumulated Other Comprehensive Income (''AOCI'') - Amount Reclassified from AOCI (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount Reclassified from AOCI
Gain (loss) on sales of securities									$ 661	$ 266	$ (6)
Interest income on taxable securities									15,836	15,211	13,724
Income tax expense	$ (2,088)	$ (4,633)	$ (4,623)	$ (4,507)	$ (5,138)	$ (4,979)	$ 31	$ (3,238)	(15,851)	(13,324)	(26,471)
Net income	5,685	11,277	11,353	12,146	13,232	12,375	915	8,809	40,461	35,331	23,828
Income before income tax	$ 7,773	$ 15,910	$ 15,976	$ 16,653	$ 18,370	$ 17,354	$ 884	$ 12,047	56,312	48,655	50,299
Unrealized Gains (Losses) on Available-for-Sale Securities and I/O Strips
Amount Reclassified from AOCI
Net of tax									466	187
Unrealized Gains (Losses) on Available-for-Sale Securities and I/O Strips \| Amount Reclassified from AOCI
Amount Reclassified from AOCI
Gain (loss) on sales of securities									661	266	(6)
Income tax expense									(195)	(79)	3
Net income									466	187	(3)
Unamortized Unrealized Gain on Available-for-Sale Securities Reclassified to Held-to-Maturity
Amount Reclassified from AOCI
Net of tax									46	31
Unamortized Unrealized Gain on Available-for-Sale Securities Reclassified to Held-to-Maturity \| Amount Reclassified from AOCI
Amount Reclassified from AOCI
Interest income on taxable securities									65	44	51
Income tax expense									(19)	(13)	(22)
Net income									46	31	29
Defined Benefit Pension Plan Items
Amount Reclassified from AOCI
Net of tax									(62)	(160)
Defined Benefit Pension Plan Items \| Amount Reclassified from AOCI
Amount Reclassified from AOCI
Other noninterest expense									(88)	(227)	(205)
Income tax benefit									26	67	86
Net of tax									(62)	(160)	(119)
Prior transition obligation \| Amount Reclassified from AOCI
Amount Reclassified from AOCI
Other noninterest expense									96	65	71
Actuarial losses \| Amount Reclassified from AOCI
Amount Reclassified from AOCI
Other noninterest expense									(184)	(292)	(276)
Accumulated Other Comprehensive Income / (Loss)
Amount Reclassified from AOCI
Net of tax									450	58
Accumulated Other Comprehensive Income / (Loss) \| Amount Reclassified from AOCI
Amount Reclassified from AOCI
Net of tax									$ 450	$ 58	$ (93)