Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(6))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=99404803&loc=d3e21409-158489

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- Definition

Amount of allowance for credit loss on reinsurance recoverable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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- Definition

Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524

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Reinsurance (Schedule of Rating for Existing Reinsurance) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	$ 6,183.9
Allowance for credit losses	(5.0)	$ (24.6)	$ (2.8)
Net reinsurance recoverable	6,178.9	6,605.4
A++ or A+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	709.3
A or A-
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	196.7
B++ or B+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	25.8
Not Rated
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	5,252.1
Ceded future policyholder benefits and expense
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	338.8
Allowance for credit losses	(0.4)
Net reinsurance recoverable	338.4	1,133.8
Ceded future policyholder benefits and expense \| A++ or A+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	328.5
Ceded future policyholder benefits and expense \| A or A-
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	4.4
Ceded future policyholder benefits and expense \| B++ or B+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	5.5
Ceded future policyholder benefits and expense \| Not Rated
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	0.4
Ceded unearned premium
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	4,953.3
Allowance for credit losses	(3.3)
Net reinsurance recoverable	4,950.0	4,565.4
Ceded unearned premium \| A++ or A+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	82.5
Ceded unearned premium \| A or A-
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	117.8
Ceded unearned premium \| B++ or B+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	17.9
Ceded unearned premium \| Not Rated
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	4,735.1
Ceded claims and benefits payable
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	823.0
Allowance for credit losses	(1.2)
Net reinsurance recoverable	821.8	846.2
Ceded claims and benefits payable \| A++ or A+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	287.6
Ceded claims and benefits payable \| A or A-
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	61.5
Ceded claims and benefits payable \| B++ or B+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	2.3
Ceded claims and benefits payable \| Not Rated
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	471.6
Ceded paid losses
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	68.8
Allowance for credit losses	(0.1)
Net reinsurance recoverable	68.7	60.0
Ceded paid losses \| A++ or A+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	10.7
Ceded paid losses \| A or A-
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	13.0
Ceded paid losses \| B++ or B+
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	0.1
Ceded paid losses \| Not Rated
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	45.0
Ceded To U.S. Government \| Not Rated
Ceded Credit Risk [Line Items]
Best Ratings of Reinsurer	$ 143.8	$ 95.8	$ 86.8