Fair Value of Financial Instruments (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 Technique	Dec. 31, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Dec. 31, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of valuation techniques	3
Transfers in or out of Level 3	$ 0
Forward exchange contracts		0	0	0	3,200,000	0	0
Money market funds		203,200,000	174,700,000	0	0	0	0
Total		$ 203,200,000	$ 174,700,000	$ 0	$ 3,200,000	$ 0	$ 0