Noncontrolling Interest - LTIP (Details) (2011 Equity Incentive Plan, LTIP Units)	3 Months Ended	0 Months Ended
Mar. 31, 2015	Jan. 12, 2015
Share-based compensation
Conversion ratio of noncontrolling units	1
Certain executive officers and independent directors
Share-based compensation
Vested units eligible for conversion	1,307,036
Outstanding awards (in shares)	1,530,105
Executive officers \| Awards vest over three years
Share-based compensation
Vesting period (in years)		3 years
Directors
Share-based compensation
Vesting period (in years)		1 year

Represents the conversion ratio of noncontrolling units.

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period eligible for conversion to common units.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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