v2.4.1.9

Net Income Per Common Unit - Additional Information (Detail) (USD $) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2015 | Mar. 31, 2014 | Jan. 31, 2008
Unit Repurchase Program [Line Items] |  |  |
Amount remaining available for repurchases | $ 335,800,000 us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1 |  |
Common stock repurchased, units | 0 us-gaap_StockRepurchasedDuringPeriodShares | 0 us-gaap_StockRepurchasedDuringPeriodShares |
Blackstone |  |  |
Unit Repurchase Program [Line Items] |  |  |
Amount authorized to repurchase under unit repurchase program |  |  | $ 500,000,000 us-gaap_StockRepurchaseProgramAuthorizedAmount1 / dei_LegalEntityAxis = us-gaap_ParentCompanyMember

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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
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