Issuance Of Notes Payable And Warrants (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended			0 Months Ended	12 Months Ended
	Aug. 21, 2008	Dec. 31, 2011 days years	Dec. 31, 2011 Class A [Member]	Dec. 31, 2010 Class A [Member]	Aug. 21, 2008 Warrants [Member] Class A [Member]	Dec. 31, 2011 Senior Notes [Member]
Issuance Of Notes Payable And Warrants [Line Items]
Principal amount of senior notes	$ 120,000	$ 120,000
Principal amount of senior notes due, year	2020
Senior notes coupon interest	5.20%
Number of class A shares issued from treasury stock			31,014,265	21,497,691	5,455
Class A shares purchase price per share					$ 22.00
Senior notes effective yield		7.94%
Long-term debt fair value senior notes						$ 23,000
Event of default under the indenture accreted amount due and payable, percentage						33.33%
Maximum number of days in which senior note will be redeemable at the accreted amount		90
Number of years after termination in which Senior Notes or Warrants be transferred under agreement		1