CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) (USD $)	12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Common Class A [Member]
Dividends declared, per share (in dollars per share)	$ 0.288	$ 0.58	$ 0.26
Common Class B [Member]
Dividends declared, per share (in dollars per share)	$ 0.24	$ 0.48	$ 0.22