Recent Accounting Standards - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease, right of use asset	$ 40.4
Operating lease liability	$ 42.0
ASU 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease, right of use asset		$ 46.7
Operating lease liability		$ 48.2