Equity and Capital - Accumulated Other Comprehensive Income (Loss) (Details) (Parent Company [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Accumulated Other Comprehensive Income Loss [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (71,429)
Other Comprehensive Income (Loss), Net of Tax	2,336	2,367
Accumulated Other Comprehensive Income (Loss), Net of Tax	(69,083)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	9
Other Comprehensive Income (Loss), Net of Tax	(16)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(7)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Other Comprehensive Income (Loss), Net of Tax	2,346	2,362
Loss on Settlement of Derivative Instruments [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(71,438)
Other Comprehensive Income (Loss), Net of Tax	2,362
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (69,076)