|
Acquisitions Pro forma results (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2012
|
Dec. 31, 2011
|
Dec. 31, 2010
|
|
| Business Combinations [Abstract] | |||
| Revenue | $ 792,626 | $ 738,918 | $ 638,283 |
| Net income attributable to common unitholders | $ 41,951 | $ 47,511 | $ 28,438 |
| Net income per common unit - basic (in dollars per share) | $ 1.41 | $ 1.88 | $ 1.13 |
| Net income per common unit - diluted (in dollars per share) | $ 1.41 | $ 1.40 | $ 1.03 |