Redeemable Noncontrolling Interest- Summary of Changes in Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Noncontrolling Interest [Abstract]
Balance as of December 31, 2017	$ 46,923
Net income attributable to noncontrolling interest	1,986	$ 2,256
Redeemable noncontrolling interest redemption value adjustment	(1,781)	20,244
Foreign currency translation	(1,926)
Acquisition of noncontrolling interest	$ (45,202)
Balance as of December 31, 2018		$ 46,923

Amount, before tax, of income (loss) attributable to noncontrolling interest. Includes, but is not limited to, income (loss) from continuing operations, discontinued operations and equity method investments.

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Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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Adjustments to temporary equity resulting from foreign currency translation adjustments.

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