Fair Value Measurement - Additional Information (Details) - USD ($) $ in Thousands	Jan. 31, 2017	Jan. 31, 2016
Fair Value, Assets & Liabilities Measured on Recurring and Nonrecurring Basis
Notes Payable	$ 248,109	$ 240,076
Business Combination, Contingent Consideration, Liability, Current	836	1,460
Business Combination, Contingent Consideration, Liability, Noncurrent	1,549	2,289
Current portion of notes payable (Note 7)	242,921	0
Non-marketable equity securities	3,000
4.00% Debentures due 2031
Fair Value, Assets & Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of notes payable	470,965	255,487
Notes Payable	242,921	234,888
Current portion of notes payable (Note 7)	242,921	0
Notes Payable, Other Payables
Fair Value, Assets & Liabilities Measured on Recurring and Nonrecurring Basis
Notes Payable	$ 5,188	$ 5,188

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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Fair value portion of notes payable.

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Aggregate carrying value of owned private equity or other securities for which a quoted market price is not readily determinable, the value of which has been determined by management based upon fair value methods, including pricing of similar securities and valuation techniques and is included in the schedule of financial condition or the balance sheet.

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-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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