Derivative Financial Instruments Fair Value of the Company's Derivative Instruments (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Derivative Fair Value [Line Items]
Fair value of derivative asset	$ 47,685	$ 4,482
Fair value of derivative liability	8,736	4,802
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Accrued expenses [Member]
Derivative Fair Value [Line Items]
Fair value of derivative liability	1,535	3,777
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other long-term liabilities [Member]
Derivative Fair Value [Line Items]
Fair value of derivative liability	144	882
Not Designated as Hedging Instrument [Member] | Cross-currency swap [Member] | Other long-term liabilities [Member]
Derivative Fair Value [Line Items]
Fair value of derivative liability	7,057	143
Fair Value, Inputs, Level 2 [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other assets, net [Member]
Derivative Fair Value [Line Items]
Fair value of derivative asset	28,759	4,227
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivative Fair Value [Line Items]
Fair value of derivative liability	1,679	4,659
Fair Value, Inputs, Level 2 [Member] | Cross-currency swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative Fair Value [Line Items]
Fair value of derivative liability	7,057	143
Fair Value, Inputs, Level 2 [Member] | Cross-currency swap [Member] | Not Designated as Hedging Instrument [Member] | Prepaid expenses and other [Member]
Derivative Fair Value [Line Items]
Fair value of derivative asset	$ 18,926	$ 255