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

No definition available.

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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 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
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Jan. 01, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 956,816	$ 920,964
Other comprehensive income (loss) before reclassifications	8,050	(24,587)
Amounts reclassified from accumulated other comprehensive income (loss) to net income	(306)	97
Net current-period other comprehensive income (loss)	7,744	(24,490)
Ending balance	978,373	919,088
Reclassification adjustment for (gains) losses included in net income	413	(131)
Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(21,741)	(249)
Balance after reclassification adjustments				$ (1,458)
Other comprehensive income (loss) before reclassifications	13,185	(25,233)
Amounts reclassified from accumulated other comprehensive income (loss) to net income	0	0
Net current-period other comprehensive income (loss)	13,185	(25,233)
Ending balance	(8,556)	(26,691)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	0	88
Balance after reclassification adjustments				0
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income (loss) to net income	0	0
Net current-period other comprehensive income (loss)	0	0
Ending balance	0	0
Total Unrealized Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(21,741)	(161)
Balance after reclassification adjustments				(1,458)
Other comprehensive income (loss) before reclassifications	13,185	(25,233)
Amounts reclassified from accumulated other comprehensive income (loss) to net income	0	0
Net current-period other comprehensive income (loss)	13,185	(25,233)
Ending balance	(8,556)	(26,691)
Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(922)	(198)
Balance after reclassification adjustments				(240)
Other comprehensive income (loss) before reclassifications	(5,135)	646
Amounts reclassified from accumulated other comprehensive income (loss) to net income	(306)	97
Net current-period other comprehensive income (loss)	(5,441)	743
Ending balance	(6,363)	503
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(22,663)	(359)
Balance after reclassification adjustments				(1,698)
Ending balance	(14,919)	(26,188)
Retained Earnings
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	316,651	258,076
Ending balance	328,476	279,942
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 \| Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption			(298)	(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 \| Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Cumulative effect of new accounting principle in period of adoption			(1,041)	(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 \| Accumulated Other Comprehensive Loss
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
Interest Expense
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Reclassification adjustment for (gains) losses included in net income	(413)	131
Reclassification adjustment for (gains) losses in net income, after tax	$ (306)	$ 97