Supplemental Financial Statement Information - Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Supplemental Financial Statement Information [Abstract]
Net unrealized investment losses	$ (1,122)	$ (697)
Currency translation gains (losses)	(4,080)	8,794
Net unrealized gains on cash flow hedges	0	41
Total	$ (5,202)	$ 8,138

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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