Recent Accounting Pronouncements - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
ASU 2018-02
Recent Accounting Pronouncements [Line Items]
Reclassification from AOCI to accumulated deficit	$ 0.6

Tax Cuts And Jobs Act Of 2017 reclassification from Aoci to accumulated deficit

No definition available.

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