XML 61 R51.htm IDEA: XBRL DOCUMENT
v3.22.2

Reinsurance Recoverable Credit Ratings (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | --- | --- | --- | --- | ---
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance recoverable, gross | $ 573,830 |  | $ 601,668 |  |  |
Reinsurance Recoverable, Allowance for Credit Loss | (1,600) | $ (1,600) | (1,600) | $ (1,777) | $ (1,840) | $ (1,777)
Reinsurance recoverable, net of allowance for credit losses | 572,230 |  | 600,068 |  |  |
AM Best, A++ Rating [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 41,458 |  | 38,610 |  |  |
AM Best, A++ Rating [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 8 |  | 9 |  |  |
AM Best, A++ Rating [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 41,450 |  | 38,601 |  |  |
AM Best, A+ Rating [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 353,193 |  | 341,377 |  |  |
AM Best, A+ Rating [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 891 |  | 1,520 |  |  |
AM Best, A+ Rating [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 352,302 |  | 339,857 |  |  |
AM Best, A Rating [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 97,795 |  | 96,902 |  |  |
AM Best, A Rating [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 897 |  | 1,227 |  |  |
AM Best, A Rating [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 96,898 |  | 95,675 |  |  |
AM Best, A- Rating [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 2,737 |  | 3,354 |  |  |
AM Best, A- Rating [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 90 |  | 145 |  |  |
AM Best, A- Rating [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 2,647 |  | 3,209 |  |  |
AM Best, B++ Rating [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
AM Best, B++ Rating [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
AM Best, B++ Rating [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
AM Best, B+ Rating [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
AM Best, B+ Rating [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
AM Best, B+ Rating [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
AM Best Rated Reinsurer [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 495,183 |  | 480,243 |  |  |
AM Best Rated Reinsurer [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 1,886 |  | 2,901 |  |  |
AM Best Rated Reinsurer [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 493,297 |  | 477,342 |  |  |
Total federal and state pools [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 74,380 |  | 116,378 |  |  |
Total federal and state pools [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 0 |  | 0 |  |  |
Total federal and state pools [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 74,380 |  | 116,378 |  |  |
Other than Federal And State Pools [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 4,267 |  | 5,047 |  |  |
Other than Federal And State Pools [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 86 |  | 450 |  |  |
Other than Federal And State Pools [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 4,181 |  | 4,597 |  |  |
Total Non Rated Reinsurer [Member] |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 78,647 |  | 121,425 |  |  |
Total Non Rated Reinsurer [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 86 |  | 450 |  |  |
Total Non Rated Reinsurer [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 78,561 |  | 120,975 |  |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | 1,972 |  | 3,351 |  |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Reinsurance Recoverables, Gross | $ 571,858 |  | $ 598,317 |  |  |

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_ReinsuranceRecoverableCreditQualityIndicatorLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6824-158387 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
Name: | us-gaap_ReinsuranceRecoverables
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -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 + Details
Name: | us-gaap_ReinsuranceRecoverablesAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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 + Details
Name: | us-gaap_ReinsuranceRecoverablesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6824-158387 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=99404803&loc=d3e21412-158489 + Details
Name: | us-gaap_ReinsuranceRecoverablesOnUnpaidLossesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_CreditRatingAMBestAxis=srt_AMBestAPlusPlusRatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingAMBestAxis=srt_AMBestAPlusRatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingAMBestAxis=srt_AMBestARatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingAMBestAxis=srt_AMBestAMinusRatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingAMBestAxis=srt_AMBestBPlusPlusRatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingAMBestAxis=srt_AMBestBPlusRatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CreditRatingAMBestAxis=sigi_AMBestRatedReinsurerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | sigi_NonRatedReinsurerAxis=sigi_TotalfederalandstatepoolsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | sigi_NonRatedReinsurerAxis=sigi_OtherFederalAndStatePoolsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | sigi_NonRatedReinsurerAxis=sigi_TotalNonRatedReinsurerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | sigi_ReinsuranceRecoverableAxis=sigi_ReinsuranceRecoverableforPaidandUnpaidClaimsandClaimsAdjustmentsGrossMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |