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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Increase (decrease) in valuation allowance		$ (59.5)	$ 3.9	$ 11.8
Earliest Tax Year | California Franchise Tax Board
Income Tax Disclosure [Line Items]
Tax returns year remain subject to examination by the taxing jurisdictions		1998
Earliest Tax Year | Tax and Customs Administration, Netherlands
Income Tax Disclosure [Line Items]
Tax returns year remain subject to examination by the taxing jurisdictions		2014
Earliest Tax Year | Domestic Tax Authority
Income Tax Disclosure [Line Items]
Tax returns year remain subject to examination by the taxing jurisdictions		1998
Latest Tax Year | California Franchise Tax Board
Income Tax Disclosure [Line Items]
Tax returns year remain subject to examination by the taxing jurisdictions		2016
Latest Tax Year | Tax and Customs Administration, Netherlands
Income Tax Disclosure [Line Items]
Tax returns year remain subject to examination by the taxing jurisdictions		2016
Latest Tax Year | Domestic Tax Authority
Income Tax Disclosure [Line Items]
Tax returns year remain subject to examination by the taxing jurisdictions		2016
Scenario, Forecast
Income Tax Disclosure [Line Items]
Change in statutory tax rate on income	21.00%

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Income Tax Disclosure [Line Items]

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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Amount of increase (decrease) in allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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