CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) (USD $)	Jul. 31, 2011	Jan. 31, 2011
CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited)
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, share authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, share outstanding (in shares)	0	0
Common stock, par value ( in dollars per share)	$ 0.001	$ 0.001
Common stock, share authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	17,683,020	17,683,020
Treasury stock, (in shares)	1,510,843	1,721,601
Common Class A [Member]
CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited)
Common stock, par value ( in dollars per share)	$ 0.001	$ 0.001
Common stock, share authorized (in shares)	71,000,000	71,000,000
Common stock, shares issued (in shares)	14,146,416	14,146,416
Common Class B [Member]
CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited)
Common stock, par value ( in dollars per share)	$ 0.001	$ 0.001
Common stock, share authorized (in shares)	4,000,000	4,000,000
Common stock, shares issued (in shares)	3,536,604	3,536,604