|
Fair Value Measurements and Marketable Securities - Marketable Securities with Unrealized Losses (Detail) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2012
|
|---|---|
| Schedule of Available-for-sale Securities [Line Items] | |
| Marketable securities, in loss position for less than twelve months, Fair Value | $ 7,567 |
| Marketable securities, in loss position for less than twelve months, Unrealized Loss | (7) |
|
Government securities [Member]
|
|
| Schedule of Available-for-sale Securities [Line Items] | |
| Marketable securities, in loss position for less than twelve months, Fair Value | 1,118 |
| Marketable securities, in loss position for less than twelve months, Unrealized Loss | (6) |
|
Corporate debt securities [Member]
|
|
| Schedule of Available-for-sale Securities [Line Items] | |
| Marketable securities, in loss position for less than twelve months, Fair Value | 6,449 |
| Marketable securities, in loss position for less than twelve months, Unrealized Loss | $ (1) |
| X | ||||||||||
|
- Definition
Amount of the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Details
|