Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Net income	$ 138,634	$ 83,387	$ 28,584
Other comprehensive income (loss), net of tax:
Change in unrealized gain (loss) on derivative instruments	193	(203)	1,585
Change in accumulated translation adjustment	(3,110)	(3,149)	1,595
Change in pension liability	(420)	212	2,349
Comprehensive income	135,297	80,247	34,113
Net Income (Loss) Attributable to Noncontrolling Interest	(102)	(485)	0
Change in Accumulated Translation Adjustment Attributable to Noncontrolling Interest	(56)	(127)	0
Less: comprehensive loss attributable to the noncontrolling interest	(158)	(612)	0
Comprehensive income attributable to Mentor	$ 135,455	$ 80,859	$ 34,113