Accumulated Other Comprehensive Income (Loss) (Accumulated Other Comprehensive Income (Loss), Net of Tax) (Details) (USD $)
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive income (loss) at beginning of period $ (31,789,000) $ (3,212,000)
Other comprehensive income (loss):    
Other comprehensive income (loss), before reclassifications, net of tax (15,981,000) 1,560,000
Reclassification for net (gain) loss from accumulated other comprehensive income (loss), current period, net of tax (224,000) 299,000
Other comprehensive income (loss), net of tax effect (16,205,000) 1,859,000
Accumulated other comprehensive income (loss), at end of period (47,994,000) (1,353,000)
Other Comprehensive Income (Loss), Tax [Abstract]    
Tax benefit (expense) related to foreign currency translation adjustment 1,560,000 (161,000)
Cumulative translation reclassification adjustment, no tax effect 0 0
Tax benefit (expense) related to available-for-sale investments, before reclassification adjustments (155,000) (57,000)
Tax benefit (expense) of reclassification adjustment for sale of securities included in net income (2,000) (1,000)
Tax benefit (expense) related to unrealized gain (loss) on cash flow hedges arising during the period (476,000) (550,000)
Tax benefit (expense) of reclassification adjustment on cash flow hedges included in net income (137,000) 185,000
Accumulated Translation Adjustment [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive income (loss) at beginning of period (31,312,000) (2,879,000)
Other comprehensive income (loss):    
Other comprehensive income (loss), before reclassifications, net of tax (17,003,000) 569,000
Reclassification for net (gain) loss from accumulated other comprehensive income (loss), current period, net of tax 0 0
Other comprehensive income (loss), net of tax effect (17,003,000) 569,000
Accumulated other comprehensive income (loss), at end of period (48,315,000) (2,310,000)
Accumulated Net Unrealized Investment Gain (Loss) [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive income (loss) at beginning of period (129,000) 63,000
Other comprehensive income (loss):    
Other comprehensive income (loss), before reclassifications, net of tax 251,000 93,000
Reclassification for net (gain) loss from accumulated other comprehensive income (loss), current period, net of tax (3,000) [1] (2,000) [2]
Other comprehensive income (loss), net of tax effect 248,000 [3] 91,000 [4]
Accumulated other comprehensive income (loss), at end of period 119,000 154,000
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Accumulated other comprehensive income (loss) at beginning of period (348,000) (396,000)
Other comprehensive income (loss):    
Other comprehensive income (loss), before reclassifications, net of tax 771,000 898,000
Reclassification for net (gain) loss from accumulated other comprehensive income (loss), current period, net of tax (221,000) [5] 301,000 [6]
Other comprehensive income (loss), net of tax effect 550,000 [3] 1,199,000 [4]
Accumulated other comprehensive income (loss), at end of period $ 202,000 $ 803,000
[1] The before-tax gain of $5 was included in other expense, net on the condensed consolidated statements of income.
[2] The before-tax loss of $3 was included in other expense, net on the condensed consolidated statements of income.
[3] The tax expense related to the net gain reclassified from accumulated other comprehensive income (loss) was included in income tax provision on the condensed consolidated statements of income.
[4] The tax benefit related to the net loss reclassified from accumulated other comprehensive income (loss) was included in income tax provision on the condensed consolidated statements of income.
[5] The before-tax gain of $87 and $271 were included in cost of service revenues and operating expenses, primarily research and development expense, respectively on the condensed consolidated statements of income.
[6] The before-tax losses of $120 and $366 were included in cost of service revenues and operating expenses, primarily research and development expense, respectively on the condensed consolidated statements of income.