STOCKHOLDERS' EQUITY (Tables)

12 Months Ended

Jan. 31, 2015

Stockholders' Equity Note [Abstract]

Schedule of restricted stock

	Awards Outstanding			Weighted Average Grant Date Fair Value
Unvested as of January 31, 2013		1,056,731		$	29.01
Granted		315,750		$	51.96
Vested		(236,316	)	$	22.04
Canceled		(15,988	)	$	29.01
Unvested as of January 31, 2014		1,120,177		$	36.95
Granted		261,085		$	68.51
Vested		(333,531	)	$	28.16
Canceled		(2,025	)	$	54.88
Unvested as of January 31, 2015		1,045,706		$	47.59

Schedule of information regarding stock options

	2015					2014					2013
	Shares			Weighted Average Exercise		Shares			Weighted Average Exercise		Shares			Weighted Average Exercise
Stock options outstanding at beginning of year		268,488		$	22.21		382,054		$	20.79		417,722		$	16.59
Exercised		(33,900	)	$	21.51		(109,766	)	$	17.36		(120,518	)	$	11.82
Granted		—		$	—		—		$	—		85,000		$	28.72
Cancelled or forfeited		—		$	—		(3,800	)	$	19.39		(150	)	$	18.40
Stock options outstanding at end of year		234,588		$	22.32		268,488		$	22.21		382,054		$	20.79
Exercisable		125,088		$	17.26		159,238		$	18.65		224,121		$	16.89

Schedule of information about stock options outstanding

Range of Exercise Prices	Number Outstanding as of January 31, 2015		Weighted Average Remaining Contractual Life		Weighted Average Exercise Price		Number Exercisable as of January 31, 2015		Weighted Average Exercise Price
$8.00  –  $12.00		11,400		3.41	$	10.18		11,400	$	10.18
$12.01  –  $16.00		49,100		3.07	$	13.55		49,100	$	13.55
$16.01  –  $40.00		174,088		5.91	$	25.58		64,588	$	21.32
		234,588						125,088

Schedule of weighted average assumptions used in black-scholes option pricing model

	2013
Expected stock price volatility	58.2%  –  68.5%
Expected lives of options
Directors and officers	7 years
Employees	6 years
Risk-free interest rate	0.3%  –  0.6%
Expected dividend yield	0%