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Significant Transactions - NSM (Details) - Discontinued Operations, Held-for-sale - NSM Insurance Group - USD ($) $ in Millions |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Aug. 01, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Other Significant Noncash Transactions [Line Items] |  |  |  |  |  |
Gain on transaction |  |  | $ 0.0 | $ 0.0 | $ 0.0 | $ 28.7
Forecast |  |  |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |  |  |
Gain on transaction |  | $ 870.0 |  |  |  |
Subsequent Event |  |  |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |  |  |
Expected net proceeds | $ 1,400.0 |  |  |  |  |

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- Definition Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2443-110228 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 + Details
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