Financial Instruments (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | |
Sep. 30, 2015 | Sep. 30, 2015 | Dec. 31, 2014 |
Foreign Exchange Contract | | | |
Fair Value Measurements | | | |
Assets related to derivative instruments | $ 0 | $ 0 | |
Liabilities related to derivative instruments | 0 | 0 | |
Notional principal amount of foreign exchange contracts | 6,900 | 6,900 | |
Foreign Exchange Contract | Other Income Expense | Not Designated as Hedging Instrument | | | |
Fair Value Measurements | | | |
Foreign exchange contracts | 418 | $ 318 | |
Minimum | | | |
Fair Value Measurements | | | |
Maturity period of long-term investments | | 1 year | |
Maximum | | | |
Fair Value Measurements | | | |
Maturity period of long-term investments | | 2 years | |
Level 1 | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | 7,081 | $ 7,081 | |
Assets, Unrealized Gains | 3 | 3 | |
Assets, Fair Value | 7,084 | 7,084 | |
Level 1 | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Assets, Fair Value | 6,083 | 6,083 | |
Level 1 | Long-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | 1,001 | 1,001 | |
Level 1 | Money market funds | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | 6,083 | 6,083 | |
Assets, Fair Value | 6,083 | 6,083 | |
Level 1 | Money market funds | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Assets, Fair Value | 6,083 | 6,083 | |
Level 1 | U.S. government notes | | | |
Fair Value Measurements | | | |
Adjusted cost, Available-for-sale investments | 998 | 998 | |
Unrealized Gains, available-for-sale investments | 3 | 3 | |
Fair value, Available-for-sale investments | 1,001 | 1,001 | |
Level 1 | U.S. government notes | Long-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 1,001 | 1,001 | |
Level 2 | Available-for-sale investments | | | |
Fair Value Measurements | | | |
Adjusted cost, Available-for-sale investments | 66,323 | 66,323 | |
Unrealized Gains, available-for-sale investments | 29 | 29 | |
Unrealized Losses, available-for-sale investments | (14) | (14) | |
Fair value, Available-for-sale investments | 66,338 | 66,338 | |
Level 2 | Available-for-sale investments | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 1,700 | 1,700 | |
Level 2 | Available-for-sale investments | Short-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 43,977 | 43,977 | |
Level 2 | Available-for-sale investments | Long-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 20,661 | 20,661 | |
Level 2 | Asset-backed securities | | | |
Fair Value Measurements | | | |
Adjusted cost, Available-for-sale investments | 8,099 | 8,099 | |
Unrealized Gains, available-for-sale investments | 8 | 8 | |
Fair value, Available-for-sale investments | 8,107 | 8,107 | |
Level 2 | Asset-backed securities | Long-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 8,107 | 8,107 | |
Level 2 | Corporate bonds | | | |
Fair Value Measurements | | | |
Adjusted cost, Available-for-sale investments | 49,368 | 49,368 | |
Unrealized Gains, available-for-sale investments | 17 | 17 | |
Unrealized Losses, available-for-sale investments | (14) | (14) | |
Fair value, Available-for-sale investments | 49,371 | 49,371 | |
Level 2 | Corporate bonds | Short-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 37,825 | 37,825 | |
Level 2 | Corporate bonds | Long-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 11,546 | 11,546 | |
Level 2 | Commercial paper | | | |
Fair Value Measurements | | | |
Adjusted cost, Available-for-sale investments | 5,349 | 5,349 | |
Fair value, Available-for-sale investments | 5,349 | 5,349 | |
Level 2 | Commercial paper | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 1,700 | 1,700 | |
Level 2 | Commercial paper | Short-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 3,649 | 3,649 | |
Level 2 | U.S. agency securities | | | |
Fair Value Measurements | | | |
Adjusted cost, Available-for-sale investments | 3,507 | 3,507 | |
Unrealized Gains, available-for-sale investments | 4 | 4 | |
Fair value, Available-for-sale investments | 3,511 | 3,511 | |
Level 2 | U.S. agency securities | Short-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 2,503 | 2,503 | |
Level 2 | U.S. agency securities | Long-term investments | | | |
Fair Value Measurements | | | |
Fair value, Available-for-sale investments | 1,008 | 1,008 | |
Measured on a recurring basis | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | 84,358 | 84,358 | $ 97,266 |
Assets, Unrealized Gains | 32 | 32 | 2 |
Assets, Unrealized Losses | (14) | (14) | (49) |
Assets, Fair Value | 84,376 | 84,376 | 97,219 |
Measured on a recurring basis | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Assets, Fair Value | 18,737 | 18,737 | 29,187 |
Measured on a recurring basis | Short-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | 43,977 | 43,977 | 53,523 |
Measured on a recurring basis | Long-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | 21,662 | 21,662 | 14,509 |
Measured on a recurring basis | Cash | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | 10,954 | 10,954 | 13,077 |
Assets, Fair Value | 10,954 | 10,954 | 13,077 |
Measured on a recurring basis | Cash | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Assets, Fair Value | $ 10,954 | $ 10,954 | 13,077 |
Measured on a recurring basis | Level 1 | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 16,110 |
Assets, Fair Value | | | 16,110 |
Measured on a recurring basis | Level 1 | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 16,110 |
Measured on a recurring basis | Level 1 | Money market funds | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 16,110 |
Assets, Fair Value | | | 16,110 |
Measured on a recurring basis | Level 1 | Money market funds | Cash and Cash Equivalents | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 16,110 |
Measured on a recurring basis | Level 2 | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 68,079 |
Assets, Unrealized Gains | | | 2 |
Assets, Unrealized Losses | | | (49) |
Assets, Fair Value | | | 68,032 |
Measured on a recurring basis | Level 2 | Short-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 53,523 |
Measured on a recurring basis | Level 2 | Long-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 14,509 |
Measured on a recurring basis | Level 2 | Asset-backed securities | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 4,458 |
Assets, Unrealized Losses | | | (3) |
Assets, Fair Value | | | 4,455 |
Measured on a recurring basis | Level 2 | Asset-backed securities | Long-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 4,455 |
Measured on a recurring basis | Level 2 | Corporate bonds | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 54,321 |
Assets, Unrealized Gains | | | 2 |
Assets, Unrealized Losses | | | (46) |
Assets, Fair Value | | | 54,277 |
Measured on a recurring basis | Level 2 | Corporate bonds | Short-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 46,726 |
Measured on a recurring basis | Level 2 | Corporate bonds | Long-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 7,551 |
Measured on a recurring basis | Level 2 | Commercial paper | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 6,797 |
Assets, Fair Value | | | 6,797 |
Measured on a recurring basis | Level 2 | Commercial paper | Short-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | 6,797 |
Measured on a recurring basis | Level 2 | U.S. agency securities | | | |
Fair Value Measurements | | | |
Assets, Adjusted Cost | | | 2,503 |
Assets, Fair Value | | | 2,503 |
Measured on a recurring basis | Level 2 | U.S. agency securities | Long-term investments | | | |
Fair Value Measurements | | | |
Assets, Fair Value | | | $ 2,503 |