Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9038-108599

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Business Segment, Geographic Area, Product and Significant Customer Information - Schedule of Net Revenues and Long-Lived Assets by Geographic Regions (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 511,800	$ 486,267	$ 480,757	$ 437,153	$ 405,140	$ 380,660	$ 325,861	$ 183,681	$ 1,915,977	$ 1,295,342	$ 813,524
Long-lived assets	203,154				200,670				203,154	200,670
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									955,284	675,601	458,313
Long-lived assets	124,689				122,547				124,689	122,547
South Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									212,763	112,432	106,909
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									167,318	96,954	62,879
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									209,912	156,365	79,927
Long-lived assets	28,820				28,717				28,820	28,717
Asia (Excluding Korea and Japan) [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									370,700	253,990	$ 105,496
Long-lived assets	$ 49,645				$ 49,406				$ 49,645	$ 49,406