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	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Jan. 01, 2019	Jan. 01, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	$ (38,784)
Accumulated Other Comprehensive Income (Loss), ending balance	(37,127)		$ (37,127)
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	$ 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					0	(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	0
AOCI Attributable to Parent
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	$ (41,028)
Accumulated Defined Benefit Plans Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	(24,923)	$ (17,790)	(18,475)	$ (24,457)
Other Comprehensive Income (Loss) before Reclassifications	0	0	(4,589)	7,951
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(1,078)	(685)	(2,937)	(1,969)
Accumulated Other Comprehensive Income (Loss), ending balance	(26,001)	(18,475)	(26,001)	(18,475)
Accumulated Net Unrealized Investment Gain (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	(2,942)	40,190	(2,593)	32,872
Other Comprehensive Income (Loss) before Reclassifications	1,973	(2,159)	892	11,927
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	662	404	1,394	(6,364)
Accumulated Other Comprehensive Income (Loss), ending balance	(307)	(2,593)	(307)	(2,593)
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	(10,919)	(11,342)	(11,253)	(11,599)
Other Comprehensive Income (Loss) before Reclassifications	0	0	0	0
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	100	89	434	346
Accumulated Other Comprehensive Income (Loss), ending balance	(10,819)	(11,253)	(10,819)	(11,253)
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), beginning balance	(38,784)	11,058	(32,321)	(3,184)
Other Comprehensive Income (Loss) before Reclassifications	1,973	(2,159)	(3,697)	19,878
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(316)	(192)	(1,109)	(7,987)
Accumulated Other Comprehensive Income (Loss), ending balance	$ (37,127)	$ (32,321)	$ (37,127)	$ (32,321)