Equity-Based Compensation, Profit Sharing and Deferred Compensation Plans - Black-Scholes Option-Pricing Model Assumptions (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Estimated option life	5 years 2 months 12 days	4 years 11 months 12 days	4 years 9 months 15 days
Risk free interest rate (range), minimum	0.42%	0.35%	0.44%
Risk free interest rate (range), maximum	2.10%	1.84%	2.86%
Expected volatility (range), minimum	17.98%	17.71%	31.29%
Expected volatility (range), maximum	32.72%	34.43%	37.43%
Expected dividend rate	0.00%	0.00%	0.00%
Weighted average grant- date fair value per share of options granted	$ 268.13	$ 221.45	$ 230.38