|
Capital Stock (Details) (USD $)
In Millions, except Share data, unless otherwise specified |
3 Months Ended | 9 Months Ended |
|---|---|---|
|
Mar. 31, 2012
|
Sep. 30, 2012
|
|
| Weighted Average Number of Shares Outstanding Reconciliation [Abstract] | ||
| Shares of Common Stock for Defined Benefit Plan Contribution | 361,446 | |
| Shares of Common Stock for Defined Benefit Plan Contribution - Value per Share | $ 24.90 | |
| Value of Shares of Common Stock for Defined Benefit Plan Contribution | $ 9.0 | $ 9.0 |
| Date of shares issued for stock contribution | Mar. 06, 2012 | |
| Discount due to lack of marketability | 2.40% | |
| Closing share price | $ 25.51 | |
| Common Stock, Value of Shelf Registration | $ 150.0 |