INCOME TAXES - Reconciliation of Expected Income Tax Expense to Actual Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
INCOME TAXES
Computed expected income tax expense			$ 29,318	$ 21,311
State income taxes, net of federal tax benefit			3,296	2,997
Permanent differences, net			(6,419)	(4,794)
Other, net			927	331
Income tax expense	$ 8,194	$ 7,045	$ 27,122	$ 19,845

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
-Paragraph 1
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6515339

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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