Stock-Based Compensation and Stock Awards - Schedule of Assumptions Used in Monte Carlo Simulation (Detail) - Performance Unit Awards [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility (as a percentage)	32.50%	29.50%
Risk-free interest rate (as a percentage)	1.01%	0.9795%
Grant date price (in dollars per share)	$ 48.45	$ 65.72