Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ (361,888)	$ (333,154)
Ending balance	(1,264,026)	(361,888)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	1,273	1,079
Net current period other comprehensive income (loss)	(709)	194
Reclassifications	0	0
Ending balance	564	1,273
Net Unrealized (Gains) Losses on Marketable Securities [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(10)	126
Net current period other comprehensive income (loss)	44	(136)
Reclassifications	0	0
Ending balance	34	(10)
Accumulated Other Comprehensive Loss (Income) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	1,263	1,205
Net current period other comprehensive income (loss)	(665)	58
Reclassifications	0	0
Ending balance	$ 598	$ 1,263

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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 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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