Acquisitions Acquisitions - Schedule of pro forma information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Combinations [Abstract]
Total revenues	$ 172,355	$ 77,069	$ 330,164	$ 156,488
Net income	$ 25,940	$ 3,323	$ 36,471	$ 3,490
Net income per unit - basic and diluted	$ 0.09	$ 0.00	$ 0.13	$ 0.00

Business Acquisition, Pro Forma Earnings Per Share, Basic and Diluted

No definition available.

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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- Details

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