Fair Value of Financial Instruments Financial Instruments Carried at Fair Value (Details) (Fair Value, Inputs, Level 2 [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets carried at fair value	$ 38,364	$ 53,043
Financial liabilities carried at fair value	2,921	2,439
Interest rate swap [Member] | Designated as hedging instrument [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities carried at fair value	2,921	2,439
Interest rate swap [Member] | Other assets, net [Member] | Designated as hedging instrument [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets carried at fair value	25,869	36,987
Cross-currency swap [Member] | Prepaid expenses and other [Member] | Not Designated as Hedging Instrument [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets carried at fair value	$ 12,495	$ 16,056