Noncontrolling Interests (Preferred Stockholders' Equity in Subsidiaries) (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2010 Redeemable Preferred Stock Member	Dec. 31, 2009 Redeemable Preferred Stock Member
Minority Interest [Line Items]
Noncontrolling Interest Preferred Stock Issued Shares			300,000	3,750,000
Noncontrolling Interest Preferred Stock Issued Value			$ 300,000,000	$ 375,000,000
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			25.00%
Noncontrolling Interest, Ownership Percentage by Parent			75.00%
Opening Balance	296,370,000	296,370,000
Ending balance	296,370,000	296,370,000
Preferred Stock Variable Term Voting Redemption Expense	$ 3,000,000