A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Amount of stockholders' equity including the portion attributable to noncontrolling interests, after the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Changes in Accumulated Other Comprehensive Income (Loss) By Component (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 991,405	$ 936,227	$ 956,816	$ 920,964
Other comprehensive income (loss) before reclassifications	1,994	1,800	14,967	(30,404)
Amounts reclassified from accumulated other comprehensive income (loss) to net income	(175)	11,944	(478)	11,849
Net current-period other comprehensive income (loss)	1,819	13,744	14,489	(18,555)
Ending balance	1,019,150	954,812	1,019,150	954,812
Reclassification, available-for-sale debt securities, after tax	(5,074)	(12,602)	(33,617)	21,651
Reclassification adjustment for (gains) losses included in net income	764	(2,519)	355	(2,647)
Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	6,802	(35,711)	(21,741)	(249)
Balance after reclassification adjustments					$ (1,458)
Other comprehensive income (loss) before reclassifications	5,815	(1,206)	34,358	(35,459)
Amounts reclassified from accumulated other comprehensive income (loss) to net income	(741)	13,808	(741)	13,808
Net current-period other comprehensive income (loss)	5,074	12,602	33,617	(21,651)
Ending balance	11,876	(23,109)	11,876	(23,109)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	0	0	0	88
Balance after reclassification adjustments					0
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss) to net income	0	0	0	0
Net current-period other comprehensive income (loss)	0	0	0	0
Ending balance	0	0	0	0
Total Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	6,802	(35,711)	(21,741)	(161)
Balance after reclassification adjustments					(1,458)
Other comprehensive income (loss) before reclassifications	5,815	(1,206)	34,358	(35,459)
Amounts reclassified from accumulated other comprehensive income (loss) to net income	(741)	13,808	(741)	13,808
Net current-period other comprehensive income (loss)	5,074	12,602	33,617	(21,651)
Ending balance	11,876	(23,109)	11,876	(23,109)
Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(16,795)	1,714	(922)	(198)
Balance after reclassification adjustments					(240)
Other comprehensive income (loss) before reclassifications	(3,821)	3,006	(19,391)	5,055
Amounts reclassified from accumulated other comprehensive income (loss) to net income	566	(1,864)	263	(1,959)
Net current-period other comprehensive income (loss)	(3,255)	1,142	(19,128)	3,096
Ending balance	(20,050)	2,856	(20,050)	2,856
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(9,993)	(33,997)	(22,663)	(359)
Balance after reclassification adjustments					(1,698)
Ending balance	(8,174)	(20,253)	(8,174)	(20,253)
Retained Earnings
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	334,157	299,990	316,651	258,076
Ending balance	357,608	302,404	357,608	302,404
Accounting Standards Update 2018-02
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					0
Accounting Standards Update 2018-02 \| Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(256)
Accounting Standards Update 2018-02 \| Foreign Currency Items
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					0
Accounting Standards Update 2018-02 \| Total Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(256)
Accounting Standards Update 2018-02 \| Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(42)
Accounting Standards Update 2018-02 \| Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(298)
Accounting Standards Update 2018-02 \| Retained Earnings
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					298
Accounting Standards Update 2016-01
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					0
Accounting Standards Update 2016-01 \| Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(953)
Accounting Standards Update 2016-01 \| Foreign Currency Items
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(88)
Accounting Standards Update 2016-01 \| Total Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(1,041)
Accounting Standards Update 2016-01 \| Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					0
Accounting Standards Update 2016-01 \| Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(1,041)
Accounting Standards Update 2016-01 \| Retained Earnings
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					1,041
Combined effect of multiple accounting pronouncements on components of shareholders' equity \| Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					(1,300)
Combined effect of multiple accounting pronouncements on components of shareholders' equity \| Retained Earnings
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption					$ 1,300
Gain (Loss) on Sale of Investment Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Reclassification, available-for-sale debt securities, before tax	(1,000)	18,700	(1,000)	18,700
Reclassification, available-for-sale debt securities, after tax	(700)	13,800	(700)	13,800
Interest Expense
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Reclassification adjustment for (gains) losses included in net income	800	303	400	175
Reclassification adjustment for (gains) losses included in net income	$ 600	224	$ 300	129
Non-interest Income
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Reclassification adjustment for (gains) losses included in net income		(2,800)		(2,800)
Reclassification adjustment for (gains) losses included in net income		$ (2,100)		$ (2,100)