Stock-Based Compensation Plans and Employee Benefits - Summary of Fair Values for Stock-based Awards Granted Using Black-Scholes Option Pricing Model (Detail) - Black-Scholes Option Pricing Model [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of grants	$ 1.61	$ 2.35	$ 2.43
Risk-free interest rate (range) - Based upon the U.S. Treasury Strip with a maturity date that approximates the expected term of the award, minimum	1.10%	1.40%	1.20%
Risk-free interest rate (range) - Based upon the U.S. Treasury Strip with a maturity date that approximates the expected term of the award, maximum	1.50%	1.60%	1.40%
Expected volatility (range) - Derived by using a 50/50 blend of implied and historical changes in the Company's historical stock prices over a time frame consistent with the expected life of the award, minimum	20.60%	21.50%	24.70%
Expected volatility (range) - Derived by using a 50/50 blend of implied and historical changes in the Company's historical stock prices over a time frame consistent with the expected life of the award, maximum	22.50%	23.40%	28.50%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield (range) – Forecasted dividend yield based on the expected life	4.50%	4.10%	4.50%
Expected life (range) – Derived by referring to actual exercise experience	4 years	4 years	4 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield (range) – Forecasted dividend yield based on the expected life	5.20%	4.30%	4.60%
Expected life (range) – Derived by referring to actual exercise experience	5 years	5 years	5 years