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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
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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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- Definition 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 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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- Definition 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 + Details
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