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Indebtedness (Narrative) (Details) (USD $) In Millions, unless otherwise specified |  |  | 3 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2013 | Mar. 31, 2013 Five Point Eight Hundred Seventy Five Senior Notes due 2043 [Member] | Mar. 31, 2013 Redemption of Seven Point Fifty Percent Junior Notes [Member] | Sep. 30, 2013 Line of Credit expires September 26,2017 [Member]
Aggregate principal of notes |  | $ 185 | $ 100 |
Pre-tax write-off of remaining capitalized debt issuance costs |  |  | 3.3 |
Bond Proceeds |  | 57.1 |  |
Line of Credit Facility, Current Borrowing Capacity |  |  |  | 30
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  | $ 50
Line Of Credit Federal Home Loan Bank Maximum Borrowing Percentage Permitted | 10.00% |  |  |

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- Definition The maximum collaterized borrowing percentage of the subsidiary's admitted assets from the Federal Home Loan Bank that are permitted by the Line of Credit. + References No definition available. + Details
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