|
Notes Payable - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
|
Sep. 30, 2012
Bank
|
Sep. 30, 2011
|
Sep. 30, 2012
Bank
|
Sep. 30, 2011
|
Dec. 31, 2011
|
|
| Notes Payable [Line Items] | |||||
| Notes payable | $ 0 | $ 0 | $ 0 | ||
| Capital investment | 4.7 | 4.7 | |||
| Dividend received | 0.1 | 0.1 | 0.1 | 0.1 | |
| Unsecured revolving line of credit | $ 60.0 | $ 60.0 | |||
| Number of major commercial banks | 2 | 2 | |||
| Debt instrument maturity date | Jun. 01, 2013 | ||||