Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accumulated Other Comprehensive Loss [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (8,446)
Other comprehensive income (loss), before income taxes	1,852	(820)
Income tax expense	(687)	303
Other comprehensive income (loss), net of income taxes	1,165	(517)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(7,281)
Cash Flow Hedging [Member]
Accumulated Other Comprehensive Loss [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(8,446)
Other comprehensive loss before reclassifications	(59)
Amounts reclassified from accumulated other comprehensive loss to interest expense	1,911
Other comprehensive income (loss), before income taxes	1,852
Income tax expense	(687)
Other comprehensive income (loss), net of income taxes	1,165
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (7,281)