Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (183,772)	$ (258,601)
Other comprehensive income (loss) before reclassification	(207)
Amounts reclassified from accumulated other comprehensive loss	215
Net current period other comprehensive income (loss)	8	1,070
Ending balance	(185,477)	(259,917)
Loss on Cash Flow Hedge
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(1,436)
Other comprehensive income (loss) before reclassification	0
Amounts reclassified from accumulated other comprehensive loss	215
Net current period other comprehensive income (loss)	215
Ending balance	(1,221)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(4,010)
Other comprehensive income (loss) before reclassification	(207)
Amounts reclassified from accumulated other comprehensive loss	0
Net current period other comprehensive income (loss)	(207)
Ending balance	(4,217)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(5,446)	(4,699)
Net current period other comprehensive income (loss)	8	1,070
Ending balance	$ (5,438)	$ (3,629)

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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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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