v3.8.0.1

Stock-Based Compensation - Additional Information (Detail) - shares | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Time-based Restricted Units [Member] |  |  |  |
Stock Based Compensation [Line Items] |  |  |  |
Restricted units awarded to managers (shares) | 26,296 | 10,992 | 472,913 | 25,280
Performance-based Restricted Units [Member] |  |  |  |
Stock Based Compensation [Line Items] |  |  |  |
Restricted units awarded to managers (shares) | 4,646 | 2,318 | 371,045 | 310,481

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- Definition Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards. + References Reference 1: 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=84159872&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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