v2.4.0.6

Notes Payable (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |  | 3 Months Ended |  | 3 Months Ended |  | 3 Months Ended |  | 3 Months Ended |  | 3 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2012 | Mar. 31, 2011 | Dec. 31, 2011 | Mar. 31, 2012 Senior Subordinated Notes [Member] Senior Notes, 6 Percent Due May 15, 2017 [Member] | Mar. 31, 2011 Senior Subordinated Notes [Member] Senior Notes, 6 Percent Due May 15, 2017 [Member] | Dec. 31, 2011 Senior Subordinated Notes [Member] Senior Notes, 6 Percent Due May 15, 2017 [Member] | Mar. 31, 2012 Senior Subordinated Notes [Member] Senior Notes, 6 Percent Due November 30, 2015 [Member] | Mar. 31, 2011 Senior Subordinated Notes [Member] Senior Notes, 6 Percent Due November 30, 2015 [Member] | Dec. 31, 2011 Senior Subordinated Notes [Member] Senior Notes, 6 Percent Due November 30, 2015 [Member] | Mar. 31, 2012 Mortgage Note Payabe at Amortized Cost [Member] | Mar. 31, 2011 Mortgage Note Payabe at Amortized Cost [Member] | Dec. 31, 2011 Mortgage Note Payabe at Amortized Cost [Member] | Mar. 31, 2012 Notes Payable under Revolving Credit Agreement | Mar. 31, 2011 Notes Payable under Revolving Credit Agreement | Mar. 31, 2012 Notes Payable under Revolving Credit Agreement 2016 Credit Agreement [Member] | Mar. 07, 2012 Notes Payable under Revolving Credit Agreement 2016 Credit Agreement [Member] | Mar. 31, 2012 Notes Payable under Revolving Credit Agreement Former Credit Agreement [Member] | Mar. 07, 2012 Notes Payable under Revolving Credit Agreement Former Credit Agreement [Member] | Dec. 31, 2011 Notes Payable under Revolving Credit Agreement Former Credit Agreement [Member]
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Notes Payable | $ 610.8 |  | $ 610.6 | $ 356.9 |  | $ 356.8 | $ 248.3 |  | $ 248.2 | $ 5.6 |  | $ 5.6 |  |  |  |  |  |  |
Notes Payable, Interest Rate, Stated Percentage |  |  |  | 6.00% |  |  | 6.00% |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 325.0 |  | 245.0 |
Line of Credit Facility, Length of Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 325.0 |  |  |  |
Line of Credit Facility, Amount Outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  | 0 | 0
Write off of Deferred Debt Issuance Cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.5 |  |
Interest Expense before Capitalization of Interest | 10.5 | 9.9 |  | 5.5 | 5.5 |  | 3.9 | 3.8 |  | 0.1 | 0.1 |  | 1.0 | 0.5 |  |  |  |  |
Capitalization of Interest | (0.8) | (0.5) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest Expense | 9.7 | 9.4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest Paid | $ 1.8 | $ 0.3 |  |  |  |  |  |  |  | $ 0.1 | $ 0.1 |  | $ 1.7 | $ 0.2 |  |  |  |  |

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