Redeemable Preferred Stock (Detail) (USD $)	0 Months Ended	12 Months Ended			0 Months Ended		1 Months Ended	12 Months Ended		3 Months Ended	12 Months Ended
	May 02, 2013	Feb. 28, 2014	Feb. 28, 2013	Feb. 29, 2012	Sep. 19, 2012 Termination of Total Returns Swaps	Apr. 02, 2012 2012 Retention Plan	Apr. 30, 2012 2012 Retention Plan	Feb. 28, 2014 Voting And Transfer Restriction Agreement	Feb. 28, 2013 Voting And Transfer Restriction Agreement	Jan. 31, 2012 Swap and Voting Agreement	Feb. 29, 2012 Swap and Voting Agreement	Feb. 28, 2014 Series A preferred stock
Temporary Equity [Line Items]
Liquidation preference per share of preferred stock		$ 50.00
Conversion price, per share		$ 20.495
Number of shares of Class A common stock converted for each share of Preferred Stock		2.44						2.44
Redemption of preferred stock for cash at liquidation preference per share, percentage		100.00%
Aggregate liquidation preference		$ 46,500,000
Authorized share repurchase amount	500,000.0
Shares repurchased												8,650
Shares repurchased, average cost per share		$ 12.38
Gain on extinguishment of stock		300,000
Contribution of preferred stock to trust						400,000	400,000
Distribution period						2 years
Number of preferred shares allocated to individual employees		0
Stock based compensation expense		4,884,000	2,942,000	1,092,000				2,200,000	700,000
Number of shares Entity have the ability to direct vote								400,000			1,484,679
Right to exchange, number of convertible preferred stock								400,000
Preferred Stock right purchased					1,484,679					1,871,529
Preferred Stock, weighted average price										$ 15.64
Preferred Stock, shares purchased and retired										386,850
Percent of shares Entity have the ability to direct vote											61.00%
Gain on extinguishment of preferred stock											$ 61,900,000
Preferred Stock outstanding		1,328,991	1,337,641