Business Segments - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Segment	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable business segments | Segment	2
Corporate Costs, Including Other Income (Expense) [Member]
Segment Reporting Information [Line Items]
Internal reorganization associated costs | $	$ 2,400	$ 1,600