| **Fair Value of Financial Instruments (Details) (USD $)In Thousands, unless otherwise specified** | Sep. 30, 2012 | Dec. 31, 2011 |
|---------------------------------------------------------------------------------------------------|---------------|---------------|
| **Long-term debt [Abstract]**                                                                     |          |          |
| Long-term debt                                                                                    | $ 8,257,599   | $ 8,205,841   |
| Carrying Amount [Member]                                                                          |          |          |
| **Long-term debt [Abstract]**                                                                     |          |          |
| Long-term debt                                                                                    | 8,257,599     | 8,205,841     |
| Fair Value [Member]                                                                               |          |          |
| **Long-term debt [Abstract]**                                                                     |          |          |
| Long-term debt                                                                                    | $ 8,650,919   | $ 7,958,873   |

| X                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_LongTermDebtAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5
+ Details**Name:**us-gaap_LongTermDebtNoncurrent**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |