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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- Definition

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.

+ References

No definition available.

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- Definition

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

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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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- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Other Comprehensive Income (Loss) - Activity in AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances at Beginning			$ 576,202	$ 549,405
Net current-period other comprehensive (loss) income	$ (5,501)	$ 909	(23,706)	4,394
Balances at Ending	599,144	589,868	599,144	589,868
Available-for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances at Beginning	(31,800)	(4,887)	(13,005)	(7,915)
Other comprehensive income (loss) before reclassifications	(5,806)	426	(24,444)	3,454
Amounts reclassified from accumulated other comprehensive (loss) income	(23)	254	(245)	254
Net current-period other comprehensive (loss) income	(5,829)	680	(24,689)	3,708
Balances at Ending	(37,629)	(4,207)	(37,629)	(4,207)
Employee Benefit Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances at Beginning	(37,636)	(28,737)	(38,291)	(29,194)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive (loss) income	328	229	983	686
Net current-period other comprehensive (loss) income	328	229	983	686
Balances at Ending	(37,308)	(28,508)	(37,308)	(28,508)
Accumulated Other Comprehensive (Loss) Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances at Beginning	(69,436)	(33,624)	(51,296)	(37,109)
Other comprehensive income (loss) before reclassifications	(5,806)	426	(24,444)	3,454
Amounts reclassified from accumulated other comprehensive (loss) income	305	483	738	940
Net current-period other comprehensive (loss) income	(5,501)	909	(23,706)	4,394
Balances at Ending	$ (74,937)	$ (32,715)	$ (74,937)	$ (32,715)
Accounting Standards Update 2016-01
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of new accounting principle					$ 65	$ 0
Accounting Standards Update 2016-01 \| Available-for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of new accounting principle						65
Accounting Standards Update 2016-01 \| Employee Benefit Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of new accounting principle						0
Accounting Standards Update 2016-01 \| Accumulated Other Comprehensive (Loss) Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of new accounting principle						$ 65