Quarterly report pursuant to Section 13 or 15(d)

Unsecured Lines of Credit Payable (Repayments and Borrowings on Unsecured Lines of Credit) (Details)

 v2.3.0.11
Unsecured Lines of Credit Payable (Repayments and Borrowings on Unsecured Lines of Credit) (Details) (USD $)
In Millions
6 Months Ended
Jun. 30, 2011
Mar. 31, 2011
Credit Facility No. 1 [Member]
   
Balance at March 31, 2011   $ 60.0
Borrowings 14.0  
Repayments    
Balance at June 30, 2011 74.0 (60.0)
Credit Facility No. 2 [Member]
   
Balance at March 31, 2011   100.0
Borrowings 71.0  
Repayments    
Balance at June 30, 2011 $ 171.0 $ (100.0)