| **Document Information** | 12 Months Ended       |
|--------------------------|-----------------------|
||
| Document Type            | 10-K                  |
| Amendment Flag           | false                 |
| Document Period End Date | Dec. 31,         2011 |

| X                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
If the value is true, then the document as an amendment to previously-filed/accepted document.
+ References
No definition available.
+ Details**Name:**dei_AmendmentFlag**Namespace Prefix:**dei_**Data Type:**xbrli:booleanItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The end date of the period reflected on the cover page if a periodic report.  For all other reports and registration statements this will be the filing date. The format of the date is CCYY-MM-DD.
+ References
No definition available.
+ Details**Name:**dei_DocumentPeriodEndDate**Namespace Prefix:**dei_**Data Type:**xbrli:dateItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The type of document being provided (such as 10-K, 10-Q, N-1A, etc). The document type should be limited to the same value as the supporting SEC submission type. The acceptable values are as follows: S-1, S-3, S-4, S-11, F-1, F-3, F-4, F-9, F-10, 6-K, 8-K, 10, 10-K, 10-Q, 20-F, 40-F, N-1A, 485BPOS, NCSR, N-Q, and Other.
+ References
No definition available.
+ Details**Name:**dei_DocumentType**Namespace Prefix:**dei_**Data Type:**us-types:SECReportItemType**Balance Type:**na**Period Type:**duration |