Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Aug. 31, 2014	Nov. 30, 2013
Class A common stock, par value per share	$ 0.01	$ 0.01
Class A common stock, shares authorized	160,000,000	160,000,000
Class A common stock, shares issued	69,127,957	67,901,101
Class A common stock, shares outstanding	68,172,435	67,382,298
Treasury stock, shares	955,522	518,803