Income Taxes - Valuation Allowance for Deferred Tax Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of year balance	$ 283,634	$ 265,362	$ 365,035
Changes in valuation allowance charged to income	65,284	18,704	36,639
Change in enacted tax rates	0	0	(137,001)
Foreign currency translation	(164)	(440)	689
Change in valuation allowance charged to OCI	(7)	8	0
Change in valuation allowance charged to equity	1,710	0	0
End of year balance	$ 350,457	$ 283,634	$ 265,362

Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Charged To Income

No definition available.

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- Definition

Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Charged To Other Comprehensive Income

+ References

No definition available.

+ Details

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- Definition

Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Due To Change In Enacted Tax Rate

+ References

No definition available.

+ Details

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- Definition

Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation, Amount Charged to Equity

+ References

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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- Definition

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

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=116821951&loc=d3e32123-109318

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