Quarterly report pursuant to Section 13 or 15(d)

New Accounting Pronouncements - Additional Information (Detail)

v3.10.0.1
New Accounting Pronouncements - Additional Information (Detail) - USD ($)
$ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]      
Corporate income tax rate percent 21.00%   35.00%
ASU 2016-15 | Reclassified from Operating Activities to Financing Activities | June 2017 Amendment of Senior Secured Credit Facility      
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]      
Cash paid   $ 246