Investments and Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Recurring basis - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Total assets	$ 496,543	$ 398,963
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	0	0
Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Total assets	45,631	495,922
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	1,531	1,447
Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Total assets	500	500
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	0	0
Cash and cash equivalents | Cash | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	425,650	375,874
Cash and cash equivalents | Cash | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Cash and cash equivalents | Cash | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Cash and cash equivalents | Money market funds | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	70,893	23,089
Cash and cash equivalents | Money market funds | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Cash and cash equivalents | Money market funds | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Cash and cash equivalents | Corporate securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Cash and cash equivalents | Corporate securities | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	17,450	166,436
Cash and cash equivalents | Corporate securities | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Cash and cash equivalents | Government securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents		0
Cash and cash equivalents | Government securities | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents		187,496
Cash and cash equivalents | Government securities | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents		0
Available-for-sale securities | Agency securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		0
Available-for-sale securities | Agency securities | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		3,300
Available-for-sale securities | Agency securities | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		0
Available-for-sale securities | Corporate securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities	0	0
Available-for-sale securities | Corporate securities | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities	27,440	70,184
Available-for-sale securities | Corporate securities | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities	500	500
Available-for-sale securities | Government securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		0
Available-for-sale securities | Government securities | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		64,494
Available-for-sale securities | Government securities | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		0
Prepaid expenses and other current assets | Foreign currency forward contracts | Quoted Prices In Active Markets for Identical Assets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Asset derivatives	0	0
Prepaid expenses and other current assets | Foreign currency forward contracts | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Asset derivatives	741	4,012
Prepaid expenses and other current assets | Foreign currency forward contracts | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Asset derivatives	0	0
Accrued expenses and other current liabilities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Liabilities, Fair Value Disclosure [Abstract]
Foreign currency derivatives	0	0
Accrued expenses and other current liabilities | Significant Other Observable Inputs (Level 2)
Liabilities, Fair Value Disclosure [Abstract]
Foreign currency derivatives	1,531	1,447
Accrued expenses and other current liabilities | Significant Unobservable Inputs (Level 3)
Liabilities, Fair Value Disclosure [Abstract]
Foreign currency derivatives	0	0
Estimate of Fair Value Measurement
Assets, Fair Value Disclosure [Abstract]
Total assets	542,674	895,385
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	1,531	1,447
Estimate of Fair Value Measurement | Cash and cash equivalents | Cash
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	425,650	375,874
Estimate of Fair Value Measurement | Cash and cash equivalents | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	70,893	23,089
Estimate of Fair Value Measurement | Cash and cash equivalents | Corporate securities
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	17,450	166,436
Estimate of Fair Value Measurement | Cash and cash equivalents | Government securities
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents		187,496
Estimate of Fair Value Measurement | Available-for-sale securities | Agency securities
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		3,300
Estimate of Fair Value Measurement | Available-for-sale securities | Corporate securities
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities	27,940	70,684
Estimate of Fair Value Measurement | Available-for-sale securities | Government securities
Assets, Fair Value Disclosure [Abstract]
Available-for-sale securities		64,494
Estimate of Fair Value Measurement | Prepaid expenses and other current assets | Foreign currency forward contracts
Assets, Fair Value Disclosure [Abstract]
Asset derivatives	741	4,012
Estimate of Fair Value Measurement | Accrued expenses and other current liabilities
Liabilities, Fair Value Disclosure [Abstract]
Foreign currency derivatives	$ 1,531	$ 1,447