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Related party transactions (Details) (Sterling Group Parters I, L.P.) | 0 Months Ended
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Aug. 20, 2012
Sterling Group Parters I, L.P. |
Related Party Transaction [Line Items] |
Common shares distributed by Sterling to its limited and general partners | 4,626,265

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- Definition Related Party Transactions, Common Stock Distributed by Related Party to Affiliated Partners + References No definition available. + Details
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Period Type: | duration

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- Details
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Period Type: | duration