|
Long-Term Incentive Plan (Weighted-Average Grant Date Fair Values) (Details) (Management [Member], USD $)
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12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2013
|
Dec. 31, 2012
|
Dec. 31, 2011
|
|
| Long Term Incentive Plan [Line Items] | |||
| Units granted | 251,166 | ||
| Weighted-Average Grant Date Fair Value | $ 51.63 | ||
|
Equity Method [Member] | Performance Shares [Member]
|
|||
| Long Term Incentive Plan [Line Items] | |||
| Units granted | 182,798 | 214,232 | 281,180 |
| Weighted-Average Grant Date Fair Value | $ 51.49 | $ 33.57 | $ 28.52 |
|
Equity Method [Member] | Retention Awards [Member]
|
|||
| Long Term Incentive Plan [Line Items] | |||
| Units granted | 22,668 | 7,016 | 59,880 |
| Weighted-Average Grant Date Fair Value | $ 53.02 | $ 30.54 | $ 23.96 |
|
Liability Method [Member] | Performance Shares [Member]
|
|||
| Long Term Incentive Plan [Line Items] | |||
| Units granted | 45,700 | 53,558 | 70,296 |
| Weighted-Average Grant Date Fair Value | $ 51.49 | $ 33.57 | $ 34.32 |