STOCKHOLDERS' EQUITY (Detail Textuals) - USD ($)	1 Months Ended		12 Months Ended
	Dec. 31, 2015	Jun. 30, 2014	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Stockholders Equity [Line Items]
Stock split of common stock			two-for-one split
Number of common share sold		3,450,000
Number of shares sold to underwriters		450,000
Public offering price per share (in dollars per share)		$ 38.82
Net proceed from offering		$ 128,700,000		$ 128,686,000
Number of shares authorized to be repurchased under prior program	3,750,000
Number of increased authorized shares to be repurchased	5,000,000
Share repurchase description	The Company did not repurchase any shares during fiscal 2016. The Company's credit agreement permits the Company to make payments for cash dividends, stock redemptions and share repurchases subject to compliance with certain covenants.
Proceeds from exercise of stock options			$ 417,000	729,000	$ 1,906,000
Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Shares available for grant			2,135,449
Restricted Stock Units (RSUs) | Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Recognized compensation expense			$ 15,600,000	11,600,000	9,200,000
Unrecognized stock compensation related to unvested option awards			$ 42,000,000	32,200,000	26,100,000
Restricted Stock Units (RSUs) | Minimum
Stockholders Equity [Line Items]
Vesting period of awards			4 years
Restricted Stock Units (RSUs) | Minimum | Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting period of awards			3 years
Restricted Stock Units (RSUs) | Maximum
Stockholders Equity [Line Items]
Vesting period of awards			5 years
Restricted Stock Units (RSUs) | Maximum | Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting period of awards			5 years
Stock Options
Stockholders Equity [Line Items]
Vesting period of awards			10 years
Weighted average remaining term for stock options outstanding			3 years 6 months 15 days
Aggregate intrinsic value for stock options outstanding			$ 12,900,000
Aggregate intrinsic value for stock options exercisable			10,200,000
Proceeds from exercise of stock options			417,000	729,000
Intrinsic value of stock options exercised			1,700,000	2,000,000
Recognized compensation expense			153,000	$ 541,000	$ 680,000
Unrecognized stock compensation related to unvested option awards			$ 126,000
Stock Options | Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Term of option awards			10 years