Consolidated Statements of Stockholders' Equity (Parentheticals) - Retained Earnings [Member] - $ / shares	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
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