Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Right-of-use operating lease asset	$ 33.1
Operating lease liability	$ 32.4
Accounting Standards Update 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Right-of-use operating lease asset		$ 35.1
Operating lease liability		$ 34.5