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Indebtedness (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
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Mar. 31, 2013
Five Point Eight Hundred Seventy Five Senior Notes due 2043 [Member] |
Aggregate principal of notes | $ 185
Bond Proceeds | 57.1
Redemption of Seven Point Fifty Percent Junior Notes [Member] |
Aggregate principal of notes | 100
Pre-tax write-off of remaining capitalized debt issuance costs | $ 3.3

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