Commitments and Contingencies - Company's Future Principal Contractual Obligations (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2013	Jan. 31, 2013
Debt Instrument [Line Items]
Operating leases, Total	$ 12,987
Remainder of 2014	901
2015	3,001
2016	2,317
2017	2,201
2018	2,005
Thereafter	2,562
Contractual obligations, Total	482,162
Interest payments on long-term-debt, Total	59,133
Contractual obligations, Total	410,042	410,042
2014	7,018
2014	6,117
2015	27,470
2015	24,469
2016	26,786
2016	24,469
2017	416,321
2017	4,078
2018	2,005
Thereafter	2,562
2016 Extended Term Loans: Due March 10, 2016, Three-Month LIBOR Plus 4.00% [Member]
Debt Instrument [Line Items]
Contractual obligations, Total	191,101	191,101
Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Contractual obligations, Total	101,542	101,542
Revolving Credit [Member] \| Senior Subordinated Notes: Due March 15, 2016, 10.375% [Member]
Debt Instrument [Line Items]
Contractual obligations, Total	117,399
2017	117,399
Revolving Credit [Member] \| 2016 Extended Term Loans: Due March 10, 2016, Three-Month LIBOR Plus 4.00% [Member]
Debt Instrument [Line Items]
Contractual obligations, Total	191,101
2017	191,101
Revolving Credit [Member] \| Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Contractual obligations, Total	101,542
2017	$ 101,542

Interest expense long term debt in next twelve months.

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Interest expense long term debt in year two.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Amount of contractual obligation maturing after the fifth fiscal year following the latest fiscal year.

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Amount of contractual obligation maturing in the fifth fiscal year following the latest fiscal year.

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Amount of contractual obligation maturing in the fourth fiscal year following the latest fiscal year.

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Amount of contractual obligation maturing in the next fiscal year following the latest fiscal year.

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Amount of contractual obligation maturing in the second fiscal year following the latest fiscal year.

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Amount of contractual obligation maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

-Section 02

-Paragraph 22

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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