Fair Value of Financial Instruments Financial Instruments Carried at Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets carried at fair value	$ 47,685	$ 4,482
Financial liability carried at fair value	8,736	4,802
Designated as Hedging Instrument [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liability carried at fair value	1,679	4,659
Not Designated as Hedging Instrument [Member] | Fair Value, Inputs, Level 2 [Member] | Cross-currency swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liability carried at fair value	7,057	143
Prepaid expenses and other [Member] | Not Designated as Hedging Instrument [Member] | Fair Value, Inputs, Level 2 [Member] | Cross-currency swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets carried at fair value	18,926	255
Interest Rate Swap [Member] | Other assets, net [Member] | Designated as Hedging Instrument [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets carried at fair value	$ 28,759	$ 4,227