v3.7.0.1

Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Income tax expense | $ 123 | $ (4,160) | $ (7,702) | $ (2,716) |
Accounting Standards Update 2016-09 [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Deferred tax liability |  |  |  |  | $ 1,000
Income tax expense |  |  | $ 1,500 |  |
Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  |  | $ 1,000

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