New Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Right of use lease assets	$ 23,360
Lease liabilities	$ 24,121
Accounting Standards Update 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Right of use lease assets		$ 25,300
Lease liabilities		25,400
Accounting Standards Update 2016-02 | Maximum
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Cumulative effect adjustment resulting from adoption of new accounting guidance		$ 100