Fair Value Measurements - Additional Information (Detail)	9 Months Ended
Oct. 27, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value measurement, estimated liquidity horizon	5 years
Fair value measurement, estimated net trading yield rate	5.00%

Estimate remaining period the underlying assets are expected to be liquidated by the investees for investments for which net asset value per share is calculated (including by unit, membership interest, or other ownership interest unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 6A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=SL6742756-110258

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration