Indebtedness Senior Secured Notes (Details) (Senior notes, Senior Secured Notes (9.50%))	0 Months Ended
	Mar. 18, 2011
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	9.50%
2013
Debt Instrument [Line Items]
Prepayment redemption price percentages	107.125%
2014
Debt Instrument [Line Items]
Prepayment redemption price percentages	104.75%
2015 and thereafter
Debt Instrument [Line Items]
Prepayment redemption price percentages	100.00%
Change of control
Debt Instrument [Line Items]
Prepayment redemption price percentages	101.00%