CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Common Class A [Member]
Dividends declared, per share (in dollars per share)	$ 0.288	$ 0.288	$ 0.288
Common Class B [Member]
Dividends declared, per share (in dollars per share)	$ 0.24	$ 0.24	$ 0.24