CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019
Statement of Stockholders' Equity [Abstract]
Total other comprehensive income, deferred income taxes	$ 1,729	$ (3,909)	$ 467	$ (1,569)
Vesting of restricted stock units and other stock grants (in shares)	94,229	266,803	102,695	99,134
Stock appreciation rights exercised (in shares)	927	20,024	2,560	10,216
Vesting of performance share units (in shares)	529,213

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Number of non-option equity instruments exercised by participants.

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Number of shares of stock issued attributable to transactions classified as other.

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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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