|
Fair Value Measurements - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified |
Sep. 30, 2013
|
Dec. 31, 2012
|
Dec. 31, 2011
|
|---|---|---|---|
| Fair Value Disclosures [Abstract] | |||
| Financial liabilities measured on a recurring basis | $ 0 | $ 0 | $ 0 |