Fair Value (Details) (USD $) | Mar. 29, 2014 | Dec. 31, 2013 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Foreign exchange forward contract assets | $257,000 | ' |
Total assets measured and recorded at fair value | 187,352,000 | 168,078,000 |
Foreign exchange forward contracts liabilities | ' | 514,000 |
Total liabilities measured and recorded at fair value | 1,282,000 | 1,796,000 |
Liability [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Contingent consideration obligation | 1,282,000 | 1,282,000 |
Forward Contracts [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Foreign exchange forward contract assets | 257,000 | 0 |
Foreign exchange forward contracts liabilities | 0 | 514,000 |
Commercial Paper [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 0 | 49,988,000 |
Money Market Funds [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 187,095,000 | 118,090,000 |
Fair Value, Inputs, Level 1 | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total assets measured and recorded at fair value | 187,095,000 | 118,090,000 |
Total liabilities measured and recorded at fair value | 0 | 0 |
Fair Value, Inputs, Level 1 | Liability [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Contingent consideration obligation | 0 | 0 |
Fair Value, Inputs, Level 1 | Forward Contracts [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Foreign exchange forward contract assets | 0 | 0 |
Foreign exchange forward contracts liabilities | 0 | 0 |
Fair Value, Inputs, Level 1 | Commercial Paper [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 0 | 0 |
Fair Value, Inputs, Level 1 | Money Market Funds [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 187,095,000 | 118,090,000 |
Fair Value, Inputs, Level 2 | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total assets measured and recorded at fair value | 257,000 | 49,988,000 |
Total liabilities measured and recorded at fair value | 0 | 514,000 |
Fair Value, Inputs, Level 2 | Liability [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Contingent consideration obligation | 0 | 0 |
Fair Value, Inputs, Level 2 | Forward Contracts [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Foreign exchange forward contract assets | 257,000 | 0 |
Foreign exchange forward contracts liabilities | 0 | 514,000 |
Fair Value, Inputs, Level 2 | Commercial Paper [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 0 | 49,988,000 |
Fair Value, Inputs, Level 2 | Money Market Funds [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total assets measured and recorded at fair value | 0 | 0 |
Total liabilities measured and recorded at fair value | 1,282,000 | 1,282,000 |
Fair Value, Inputs, Level 3 [Member] | Liability [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Contingent consideration obligation | 1,282,000 | 1,282,000 |
Fair Value, Inputs, Level 3 [Member] | Forward Contracts [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Foreign exchange forward contract assets | 0 | 0 |
Foreign exchange forward contracts liabilities | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash equivalents | $0 | $0 |