Convertible Debentures and Credit Arrangements Schedule of Convertible Senior Debentures (Detail) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2013
|
Dec. 31, 2012
|
---|---|---|
Debt Instrument [Line Items] | ||
Convertible senior debentures | $ 49,948 | $ 48,991 |
Less: current portion | (470) | 0 |
Convertible senior debentures—non-current | 49,478 | 48,991 |
Convertible Senior Debentures due 2018 [Member]
|
||
Debt Instrument [Line Items] | ||
Convertible senior debentures | 49,478 | 48,483 |
Convertible Senior Debentures due 2024 [Member]
|
||
Debt Instrument [Line Items] | ||
Convertible senior debentures | 441 | 441 |
Convertible Senior Debentures due 2014 [Member]
|
||
Debt Instrument [Line Items] | ||
Convertible senior debentures | $ 29 | $ 67 |