Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
Feb. 28, 2018	Mar. 31, 2019	Mar. 31, 2018
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)		$ (190,500)	$ (106,399)
Other comprehensive (loss) income before reclassifications		(10,070)	27,873
Amounts reclassified from accumulated other comprehensive income	$ (19,331)	1,892	2,640
Net current-period other comprehensive income		(8,178)	30,513
Accumulated other comprehensive income (loss)		(198,678)	(95,217)
Gains and Losses on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)		834	72
Other comprehensive (loss) income before reclassifications		(723)	157
Amounts reclassified from accumulated other comprehensive income	0	155	239
Net current-period other comprehensive income		(568)	396
Accumulated other comprehensive income (loss)		266	468
Pension and Other Postretirement Benefit Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)		(138,690)	(103,844)
Other comprehensive (loss) income before reclassifications		(122)	763
Amounts reclassified from accumulated other comprehensive income	(19,331)	1,737	2,401
Net current-period other comprehensive income		1,615	3,164
Accumulated other comprehensive income (loss)		(137,075)	(120,011)
Foreign Currency Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)		(52,644)	(2,627)
Other comprehensive (loss) income before reclassifications		(9,225)	26,953
Amounts reclassified from accumulated other comprehensive income	$ 0	0	0
Net current-period other comprehensive income		(9,225)	26,953
Accumulated other comprehensive income (loss)		$ (61,869)	$ 24,326

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.

+ References

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-SubTopic 10
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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

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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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