Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	$ (3,389)	$ 521
Other comprehensive loss before reclassifications	(3,389)
Amounts reclassified from accumulated other comprehensive income (loss)	(521)
Net other comprehensive loss	(3,910)
Ending Balance	(3,389)	521
Gains and Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(2,128)	521
Other comprehensive loss before reclassifications	(2,128)
Amounts reclassified from accumulated other comprehensive income (loss)	(521)
Net other comprehensive loss	(2,649)
Ending Balance	(2,128)	521
Change in Valuation Allowance
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(1,261)	0
Other comprehensive loss before reclassifications	(1,261)
Amounts reclassified from accumulated other comprehensive income (loss)	0
Net other comprehensive loss	(1,261)
Ending Balance	$ (1,261)	$ 0