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

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- Definition

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

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- Definition

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

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Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	$ 11,058
Accumulated Other Comprehensive Income (Loss), ending balance	(38,784)	$ 11,058
Accumulated Defined Benefit Plans Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	(17,790)	(23,928)	$ (29,869)
Other Comprehensive Income (Loss) before Reclassifications	(4,589)	7,951	7,363
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(2,544)	(1,813)	(1,422)
Accumulated Other Comprehensive Income (Loss), ending balance	(24,923)	(17,790)	(23,928)
Accumulated Net Unrealized Investment Gain (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	40,190	28,463	27,765
Other Comprehensive Income (Loss) before Reclassifications	(3,240)	20,251	6,904
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	1,136	(8,524)	(6,206)
Accumulated Other Comprehensive Income (Loss), ending balance	(2,942)	40,190	28,463
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	(11,342)	(11,651)	(11,810)
Other Comprehensive Income (Loss) before Reclassifications	0	0	0
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	423	309	159
Accumulated Other Comprehensive Income (Loss), ending balance	(10,919)	(11,342)	(11,651)
Accumulated Other Comprehensive Income (Loss), Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	11,058	(7,116)	(13,914)
Other Comprehensive Income (Loss) before Reclassifications	(7,829)	28,202	14,267
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(985)	(10,028)	(7,469)
Accumulated Other Comprehensive Income (Loss), ending balance	$ (38,784)	$ 11,058	$ (7,116)
Accumulated Defined Benefit Plans Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				$ 0
Accumulated Net Unrealized Investment Gain (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				(41,028)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				0
Accumulated Other Comprehensive Income (Loss), Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				$ (41,028)