Schedule I Financial Statements of Parent Company Schedule I Financial Statements of Parent Company Balance Sheet Parenthetical (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Common Stock, Shares Authorized	250,000,000	250,000,000
Common Stock, Shares, Issued	153,779,806	136,406,306
Treasury Stock, Shares	250,236	264,567
Parent Company [Member]
Common Stock, Shares Authorized	250,000,000	250,000,000
Common Stock, Shares, Issued	153,779,806	136,406,306
Treasury Stock, Shares	250,236	264,567
Preferred Stock 3 Point 80 [Member] | Parent Company [Member]
Preferred Stock, Par or Stated Value Per Share	$ 100.00	$ 100.00
Preferred Stock, Dividend Rate, Percentage	3.80%	3.80%
Preferred Stock, Shares Issued	100,000	100,000
Preferred Stock 4 Point 50 [Member] | Parent Company [Member]
Preferred Stock, Par or Stated Value Per Share	$ 100.00	$ 100.00
Preferred Stock, Dividend Rate, Percentage	4.50%	4.50%
Preferred Stock, Shares Issued	100,000	100,000
Preferred Stock 4 Point 20 [Member] | Parent Company [Member]
Preferred Stock, Par or Stated Value Per Share	$ 100.00	$ 100.00
Preferred Stock, Dividend Rate, Percentage	4.20%	4.20%
Preferred Stock, Shares Issued	70,000	70,000
Preferred Stock 4 Point 35 [Member] | Parent Company [Member]
Preferred Stock, Par or Stated Value Per Share	$ 100.00	$ 100.00
Preferred Stock, Dividend Rate, Percentage	4.35%	4.35%
Preferred Stock, Shares Issued	120,000	120,000