|
Financial Instruments and Fair Value Measurements (Details) (USD $)
In Millions, unless otherwise specified |
6 Months Ended | |
|---|---|---|
|
Jun. 30, 2012
|
Jun. 30, 2011
|
|
|
Interest Rate Swaps [Member]
|
||
| Derivative activity | ||
| Notional amounts at January 1 | $ 1,496.5 | $ 268.1 |
| New contracts | 444.2 | |
| Acquired contracts | 71.0 | 1,337.3 |
| Matured or expired contracts | (456.0) | (9.6) |
| Notional amounts at June 30 | 1,555.7 | 1,595.8 |
|
Interest Rate Cap [Member]
|
||
| Derivative activity | ||
| Acquired contracts | 25.7 | |
| Notional amounts at June 30 | $ 25.7 | |