Authorized Classes Of Cumulative Preferred And Preference Stocks (Details) (USD $)	Dec. 31, 2012
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Number of shares authorized	20,000,000
Par value of shares	$ 0.01
Northern Indiana [Member]
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Shares outstanding	0
Cumulative Preference Without Par Value [Member] | Northern Indiana [Member]
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Number of shares authorized	3,000,000
Par value of shares	$ 0
Cumulative Preference With 50 As Par Value [Member] | Northern Indiana [Member]
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Number of shares authorized	2,000,000
Par value of shares	$ 50
Cumulative Preferred With No Par Value [Member] | Northern Indiana [Member]
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Number of shares authorized	3,000,000
Par value of shares	$ 0.0
Cumulative Preferred With A 100 Par Value [Member] | Northern Indiana [Member]
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Number of shares authorized	2,400,000
Par value of shares	$ 100
Series A Junior Participating Preferred Shares [Member]
Authorized Classes Of Cumulative Preferred And Preference Stocks [Line Items]
Number of shares authorized	4,000,000