Fair Value Measures (Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014 | Sep. 30, 2014 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | $ 115,763 | $ 232,634 | $ 118,911 |
Total liabilities measured at fair value | | 659 | 924 | |
Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 112,962 | 145,823 | 110,217 |
Total liabilities measured at fair value | | 0 | 0 | |
Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 2,801 | 86,811 | 8,694 |
Total liabilities measured at fair value | | 659 | 924 | |
Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Total liabilities measured at fair value | | 0 | 0 | |
Accrued Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total liabilities measured at fair value | | 659 | 924 | |
Accrued Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total liabilities measured at fair value | | 0 | 0 | |
Accrued Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total liabilities measured at fair value | | 659 | 924 | |
Accrued Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total liabilities measured at fair value | | 0 | 0 | |
Cash Equivalents [Member] | Money Market Funds [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 82,137 | 94,112 | 79,266 |
Cash Equivalents [Member] | Money Market Funds [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 82,137 | 94,112 | 79,266 |
Cash Equivalents [Member] | Money Market Funds [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Cash Equivalents [Member] | Money Market Funds [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Cash Equivalents [Member] | Time Deposits [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 23,600 | 45,187 | 25,167 |
Cash Equivalents [Member] | Time Deposits [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 23,600 | 45,187 | 25,167 |
Cash Equivalents [Member] | Time Deposits [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | | |
Cash Equivalents [Member] | Time Deposits [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Cash Equivalents [Member] | Certificates of Deposit [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 1,470 | |
Cash Equivalents [Member] | Certificates of Deposit [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 0 | |
Cash Equivalents [Member] | Certificates of Deposit [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 1,470 | |
Cash Equivalents [Member] | Certificates of Deposit [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 0 | |
Cash Equivalents [Member] | Repurchase Agreements [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 40,000 | |
Cash Equivalents [Member] | Repurchase Agreements [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 0 | |
Cash Equivalents [Member] | Repurchase Agreements [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 40,000 | |
Cash Equivalents [Member] | Repurchase Agreements [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 0 | |
Cash Equivalents [Member] | US Government Backed Municipal Bonds [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 5,812 | |
Cash Equivalents [Member] | US Government Backed Municipal Bonds [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 0 | |
Cash Equivalents [Member] | US Government Backed Municipal Bonds [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 5,812 | |
Cash Equivalents [Member] | US Government Backed Municipal Bonds [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | | 0 | |
Available-For-Sale Short-Term Investments [Member] | Certificates of Deposit [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 3,184 | |
Available-For-Sale Short-Term Investments [Member] | Certificates of Deposit [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 0 | |
Available-For-Sale Short-Term Investments [Member] | Certificates of Deposit [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 3,184 | |
Available-For-Sale Short-Term Investments [Member] | Certificates of Deposit [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 0 | |
Available-For-Sale Short-Term Investments [Member] | US Government Backed Municipal Bonds [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 23,598 | |
Available-For-Sale Short-Term Investments [Member] | US Government Backed Municipal Bonds [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 0 | |
Available-For-Sale Short-Term Investments [Member] | US Government Backed Municipal Bonds [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 23,598 | |
Available-For-Sale Short-Term Investments [Member] | US Government Backed Municipal Bonds [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | [1] | | 0 | |
Short-term Investments [Member] | Mutual Fund Shares [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 629 | 485 | 537 |
Short-term Investments [Member] | Mutual Fund Shares [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 629 | 485 | 537 |
Short-term Investments [Member] | Mutual Fund Shares [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Short-term Investments [Member] | Mutual Fund Shares [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Other Current Assets [Member] | Derivative Financial Instruments, Assets [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 2,492 | 12,747 | 8,694 |
Other Current Assets [Member] | Derivative Financial Instruments, Assets [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Other Current Assets [Member] | Derivative Financial Instruments, Assets [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 2,492 | 12,747 | 8,694 |
Other Current Assets [Member] | Derivative Financial Instruments, Assets [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Non Current Assets [Member] | Mutual Fund Shares [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 6,596 | 6,039 | 5,247 |
Non Current Assets [Member] | Mutual Fund Shares [Member] | Level 1 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 6,596 | 6,039 | 5,247 |
Non Current Assets [Member] | Mutual Fund Shares [Member] | Level 2 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | 0 | 0 | 0 |
Non Current Assets [Member] | Mutual Fund Shares [Member] | Level 3 [Member] | | | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | | |
Total assets measured at fair value | | $ 0 | $ 0 | $ 0 |
| |
[1] | (1) Investments have remaining maturities of less than one year. | |