Debt (Narrative) (Details) (USD $)	3 Months Ended	6 Months Ended		1 Months Ended		6 Months Ended	1 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jul. 31, 2012 Term A Facility [Member]	Mar. 31, 2012 Term A Facility [Member]	Jun. 30, 2012 Term A Facility [Member]	Sep. 30, 2014 Next Quarterly Installment Under Term A Facility September 30, 2014 [Member] Term A Facility [Member]	Jun. 30, 2012 Senior Notes Due July 15, 2021 [Member]
Debt Instrument [Line Items]
Voluntary payment on credit facility				$ 50,000,000	$ 50,000,000
Write-off of deferred financing costs	5,703,000	312,000	5,703,000			312,000
Line of credit facility periodic payment							11,875,000
Face amount of senior notes								$ 700,000,000
Interest rate		8.625%						7.75%
Maturity date of senior notes								Jul. 15, 2021