Deficit (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Balance			$ (44,378)	$ (59,485)
Net income (loss)	$ 1,372	$ (3,107)	31,111	(7,290)
Other comprehensive income	212	185	636	556
Contribution from Parent				1,900
Share-based compensation			2,260	2,336
Stock option exercised			340	66
Shares forfeited for taxes			(1,149)
Cash distributions to noncontrolling interests			(301)	(229)
Balance	(5,260)	(62,146)	(5,260)	(62,146)
Additional Paid-in Capital
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Balance			250,018	244,986
Contribution from Parent				1,900
Share-based compensation			2,260	2,336
Stock option exercised			340	66
Shares forfeited for taxes			(1,149)
Balance	251,469	249,288	251,469	249,288
Accumulated Deficit
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Balance			(287,998)	(296,826)
Net income (loss)			30,870	(7,585)
Balance	(250,907)	(304,411)	(250,907)	(304,411)
Accumulated Other Comprehensive Loss
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Balance			(6,638)	(7,826)
Other comprehensive income			636	556
Balance	(6,002)	(7,270)	(6,002)	(7,270)
Noncontrolling Interests
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Balance			240	181
Net income (loss)			241	295
Cash distributions to noncontrolling interests			(301)	(229)
Balance	180	$ 247	180	$ 247
Accounting Standards Update 2014-09
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Impact of change in accounting policy	6,221		6,221
Accounting Standards Update 2014-09 \| Accumulated Deficit
Changes in shareholders equity that are attributable to shareholders and noncontrolling interests
Impact of change in accounting policy	$ 6,221		$ 6,221

Represents the increase in additional paid-in capital associated with a contribution from parent.

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The amount of increase (decrease) in equity associated with the amount of shares forfeited for taxes.

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Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Value of stock issued as a result of the exercise of stock options.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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