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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%

X

- Definition

The cash inflow from the bond proceeds contributed to the Insurance Subsidiaries as capital.

+ References

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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.

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X

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399



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-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Name Regulation S-X (SX)

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

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