Redeemable Preferred Stock (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Apr. 04, 2016	Feb. 28, 2018	Feb. 28, 2017	Feb. 29, 2016	Feb. 16, 2016
Class of Stock [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
Modified Number Of Preferred Stock Converted Into Common Stock					2.80
LOSS ON MODIFICATION OF PREFERRED STOCK		$ 0	$ 0	$ 162
Stock based compensation expense		$ 2,654	$ 2,920	$ 4,904
Series A preferred stock
Class of Stock [Line Items]
Conversion of Preferred Stock to Class A Common Stock (In shares)	866,319
Class A Common Stock
Class of Stock [Line Items]
Conversion of Preferred Stock to Class A Common Stock (In shares)	606,423