|
Long Term Debt Outstanding (Detail) (USD $)
In Thousands, unless otherwise specified |
Sep. 30, 2012
|
Dec. 31, 2011
|
|---|---|---|
| Debt Instrument [Line Items] | ||
| Long-term debt | $ 1,249,328 | $ 1,249,281 |
|
7.456% Senior Notes Due 2018
|
||
| Debt Instrument [Line Items] | ||
| Long-term debt | 500,000 | 500,000 |
|
5.95% Senior Notes Due 2020
|
||
| Debt Instrument [Line Items] | ||
| Long-term debt | $ 749,328 | $ 749,281 |