$SIGI
Selective Insurance Group Inc Stock $sigi

$sigi Overview Financials Valuation SEC Filings Company Website

2022 Q3 Form 10-Q Financial Statement

#000023055722000019 Filed on August 04, 2022

Income Statement

Concept	2022 Q3	2022 Q2	2021 Q4
Revenue	$895.0M	$864.8M	$870.5M
YoY Change	3.47%	2.89%	9.02%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$5.522M	$7.899M	$5.369M
YoY Change	29.32%	-13.31%	-11.98%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$179.0M	$173.4M	$14.40M
YoY Change	11.3%	12.32%	-3.98%
% of Gross Profit
Operating Expenses	$835.2M	$807.7M	$738.7M
YoY Change	9.15%	18.78%	16.89%
Operating Profit
YoY Change
Interest Expense	-$14.96M	-$29.11M	-$5.147M
YoY Change	44.46%	-9968.47%	-31.37%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$52.64M	$49.90M	$123.8M
YoY Change	-43.18%	-67.43%	-22.13%
Income Tax	$10.11M	$10.38M	$24.87M
% Of Pretax Income	19.21%	20.81%	20.08%
Net Earnings	$42.53M	$39.52M	$98.98M
YoY Change	-42.3%	-67.58%	-22.1%
Net Earnings / Revenue	4.75%	4.57%	11.37%
Basic Earnings Per Share	$0.67	$0.62
Diluted Earnings Per Share	$0.66	$0.61	$1.619M
COMMON SHARES
Basic Shares Outstanding	60.33M shares	60.44M shares	60.12M shares
Diluted Shares Outstanding	60.84M shares	60.85M shares

Balance Sheet

Concept	2022 Q3	2022 Q2	2021 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$9.033M	$7.566M	$45.06M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$85.33M	$83.37M	$82.05M
YoY Change	13.76%	10.95%	5.61%
Goodwill	$7.849M	$7.849M	$7.849M
YoY Change	0.0%	0.0%	0.63%
Intangibles
YoY Change
Long-Term Investments	$7.536B	$7.586B	$8.027B
YoY Change	-4.11%	-2.19%	6.95%
Other Assets	$173.1M	$116.6M	$44.61M
YoY Change	404.35%	1224.91%	201.41%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$10.52B	$10.32B	$10.46B
YoY Change	0.75%	1.47%	7.98%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$112.2M	$102.5M	$158.4M
YoY Change	-1.3%	-0.83%	1.18%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$112.2M	$102.5M	$158.4M
YoY Change	-1.3%	-7.49%	-7.12%
LONG-TERM LIABILITIES
Long-Term Debt	$505.2M	$505.1M	$506.1M
YoY Change	0.85%	-8.32%	-8.11%
Other Long-Term Liabilities	$488.1M	$425.2M	$416.6M
YoY Change	9.76%	13.29%	29.37%
Total Long-Term Liabilities	$993.2M	$930.3M	$922.6M
YoY Change	5.04%	0.44%	5.72%
TOTAL LIABILITIES
Total Short-Term Liabilities	$112.2M	$102.5M	$158.4M
Total Long-Term Liabilities	$993.2M	$930.3M	$922.6M
Total Liabilities	$8.093B	$7.724B	$7.479B
YoY Change	7.62%	6.14%	7.62%
SHAREHOLDERS EQUITY
Retained Earnings	$2.684B	$2.661B	$2.603B
YoY Change	6.34%	7.82%	14.61%
Common Stock	$695.8M	$690.9M	$673.2M
YoY Change	4.33%	4.17%	4.05%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$627.0M	$621.0M	$608.9M
YoY Change	2.98%	2.01%	1.51%
Treasury Stock Shares			44.27M shares
Shareholders Equity	$2.428B	$2.594B	$2.983B
YoY Change
Total Liabilities & Shareholders Equity	$10.52B	$10.32B	$10.46B
YoY Change	0.75%	1.47%	7.98%

Cashflow Statement

Concept	2022 Q3	2022 Q2	2021 Q4
OPERATING ACTIVITIES
Net Income	$42.53M	$39.52M	$98.98M
YoY Change	-42.3%	-67.58%	-22.1%
Depreciation, Depletion And Amortization	$179.0M	$173.4M	$14.40M
YoY Change	11.3%	12.32%	-3.98%
Cash From Operating Activities	$242.0M	$150.8M	$228.1M
YoY Change	-3.54%	-7.0%	31.78%
INVESTING ACTIVITIES
Capital Expenditures	-$7.657M	-$6.424M	-$7.040M
YoY Change	35.96%	31.34%	67.62%
Acquisitions
YoY Change
Other Investing Activities	-$208.7M	-$132.2M	-$194.0M
YoY Change	36.02%	-7.44%	4.29%
Cash From Investing Activities	-$216.4M	-$138.6M	-$201.0M
YoY Change	36.02%	-6.22%	5.69%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-24.12M	-22.53M	-16.83M
YoY Change	-63.58%	59.32%	-202.59%
NET CHANGE
Cash From Operating Activities	242.0M	150.8M	228.1M
Cash From Investing Activities	-216.4M	-138.6M	-201.0M
Cash From Financing Activities	-24.12M	-22.53M	-16.83M
Net Change In Cash	1.467M	-10.32M	10.27M
YoY Change	-94.26%	-4747.75%	-1567.71%
FREE CASH FLOW
Cash From Operating Activities	$242.0M	$150.8M	$228.1M
Capital Expenditures	-$7.657M	-$6.424M	-$7.040M
Free Cash Flow	$249.6M	$157.2M	$235.2M
YoY Change	-2.68%	-5.88%	32.63%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Amendment Flag AmendmentFlag	false
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Entity Central Index Key EntityCentralIndexKey	0000230557
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2022-06-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-33067
	dei	Entity Registrant Name EntityRegistrantName	SELECTIVE INSURANCE GROUP, INC
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	NJ
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	22-2168890
	dei	Entity Address Address Line1 EntityAddressAddressLine1	40 Wantage Avenue
	dei	Entity Address City Or Town EntityAddressCityOrTown	Branchville
	dei	Entity Address State Or Province EntityAddressStateOrProvince	NJ
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	07890
	dei	City Area Code CityAreaCode	973
	dei	Local Phone Number LocalPhoneNumber	948-3000
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
CY2022Q3	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	60329641	shares
CY2022Q2	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	31305000	usd
CY2021Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	29460000	usd
CY2022Q2	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	32149000	usd
CY2021Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	28850000	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	55000	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	65000	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Amortized Cost After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss	32094000	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss	28785000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-50800000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-9724000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6833430000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6490753000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	6439278000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	6709976000	usd
CY2022Q2	sigi	Commercialmortgageloanfairvalue Commercialmortgageloanfairvalue	130044000	usd
CY2021Q4	sigi	Commercialmortgageloanfairvalue Commercialmortgageloanfairvalue	97598000	usd
CY2022Q2	sigi	Commercialmortgageloans Gross CommercialmortgageloansGross	137217000	usd
CY2021Q4	sigi	Commercialmortgageloans Gross CommercialmortgageloansGross	95795000	usd
CY2022Q2	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	0	usd
CY2021Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	0	usd
CY2022Q2	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	137217000	usd
CY2021Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	95795000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	255833000	usd
CY2021Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	308840000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	258515000	usd
CY2021Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	335537000	usd
CY2022Q2	us-gaap	Other Short Term Investments OtherShortTermInvestments	289219000	usd
CY2021Q4	us-gaap	Other Short Term Investments OtherShortTermInvestments	447863000	usd
CY2022Q2	us-gaap	Other Investments OtherInvestments	429546000	usd
CY2021Q4	us-gaap	Other Investments OtherInvestments	409032000	usd
CY2022Q2	us-gaap	Investments Investments	7585869000	usd
CY2021Q4	us-gaap	Investments Investments	8026988000	usd
CY2022Q2	us-gaap	Cash Cash	401000	usd
CY2021Q4	us-gaap	Cash Cash	455000	usd
CY2022Q2	us-gaap	Restricted Cash RestrictedCash	7165000	usd
CY2021Q4	us-gaap	Restricted Cash RestrictedCash	44608000	usd
CY2022Q2	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	50371000	usd
CY2021Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	48247000	usd
CY2022Q2	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	1132318000	usd
CY2021Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	958787000	usd
CY2022Q2	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	14900000	usd
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	13600000	usd
CY2022Q2	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	1117418000	usd
CY2021Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	945187000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	573830000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	601668000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	572230000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	600068000	usd
CY2022Q2	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	174575000	usd
CY2021Q4	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	183007000	usd
CY2022Q2	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	15568000	usd
CY2021Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	772000	usd
CY2022Q2	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	109467000	usd
CY2021Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	0	usd
CY2022Q2	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2660584000	usd
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	253427000	usd
CY2022Q2	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	265378000	usd
CY2022Q2	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	83367000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	82053000	usd
CY2022Q2	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	359379000	usd
CY2021Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	326915000	usd
CY2022Q2	us-gaap	Goodwill Goodwill	7849000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	7849000	usd
CY2022Q2	us-gaap	Other Assets OtherAssets	234014000	usd
CY2021Q4	us-gaap	Other Assets OtherAssets	195240000	usd
CY2022Q2	us-gaap	Assets Assets	10317673000	usd
CY2021Q4	us-gaap	Assets Assets	10461389000	usd
CY2022Q2	us-gaap	Liability For Claims And Claims Adjustment Expense Property Casualty Liability LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability	4722179000	usd
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense Property Casualty Liability LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability	4580903000	usd
CY2022Q2	us-gaap	Unearned Premiums UnearnedPremiums	1968592000	usd
CY2021Q4	us-gaap	Unearned Premiums UnearnedPremiums	1803207000	usd
CY2022Q2	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	505069000	usd
CY2021Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	506050000	usd
CY2022Q2	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	0	usd
CY2021Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	13413000	usd
CY2022Q2	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	102527000	usd
CY2021Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	121057000	usd
CY2022Q2	us-gaap	Other Liabilities OtherLiabilities	425216000	usd
CY2021Q4	us-gaap	Other Liabilities OtherLiabilities	453874000	usd
CY2022Q2	us-gaap	Liabilities Liabilities	7723583000	usd
CY2021Q4	us-gaap	Liabilities Liabilities	7478504000	usd
CY2022Q2	us-gaap	Preferred Stock Value PreferredStockValue	200000000	usd
CY2021Q4	us-gaap	Preferred Stock Value PreferredStockValue	200000000	usd
CY2022Q2	us-gaap	Common Stock Value CommonStockValue	209506000	usd
CY2021Q4	us-gaap	Common Stock Value CommonStockValue	208902000	usd
CY2022Q2	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	481380000	usd
CY2021Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	464347000	usd
CY2021Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2603472000	usd
CY2022Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-336370000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	115099000	usd
CY2022Q2	us-gaap	Treasury Stock Value TreasuryStockValue	621010000	usd
CY2021Q4	us-gaap	Treasury Stock Value TreasuryStockValue	608935000	usd
CY2022Q2	us-gaap	Stockholders Equity StockholdersEquity	2594090000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	2982885000	usd
CY2022Q2	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2021Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2022Q2	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	10317673000	usd
CY2021Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	10461389000	usd
CY2022Q2	us-gaap	Premiums Earned Net Property And Casualty PremiumsEarnedNetPropertyAndCasualty	834439000	usd
CY2021Q2	us-gaap	Premiums Earned Net Property And Casualty PremiumsEarnedNetPropertyAndCasualty	740518000	usd
	us-gaap	Premiums Earned Net Property And Casualty PremiumsEarnedNetPropertyAndCasualty	1646722000	usd
	us-gaap	Premiums Earned Net Property And Casualty PremiumsEarnedNetPropertyAndCasualty	1465478000	usd
CY2022Q2	us-gaap	Net Investment Income NetInvestmentIncome	70222000	usd
CY2021Q2	us-gaap	Net Investment Income NetInvestmentIncome	83731000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	142824000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	153447000	usd
CY2022Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-42880000	usd
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	10057000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-83232000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	15176000	usd
CY2022Q2	us-gaap	Other Income OtherIncome	3037000	usd
CY2021Q2	us-gaap	Other Income OtherIncome	6212000	usd
	us-gaap	Other Income OtherIncome	4566000	usd
	us-gaap	Other Income OtherIncome	10324000	usd
CY2022Q2	us-gaap	Revenues Revenues	864818000	usd
CY2021Q2	us-gaap	Revenues Revenues	840518000	usd
	us-gaap	Revenues Revenues	1710880000	usd
	us-gaap	Revenues Revenues	1644425000	usd
CY2022Q2	us-gaap	Incurred Claims Property Casualty And Liability IncurredClaimsPropertyCasualtyAndLiability	524868000	usd
CY2021Q2	us-gaap	Incurred Claims Property Casualty And Liability IncurredClaimsPropertyCasualtyAndLiability	421623000	usd
	us-gaap	Incurred Claims Property Casualty And Liability IncurredClaimsPropertyCasualtyAndLiability	1019104000	usd
	us-gaap	Incurred Claims Property Casualty And Liability IncurredClaimsPropertyCasualtyAndLiability	835024000	usd
CY2022Q2	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	173381000	usd
CY2021Q2	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	154357000	usd
	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	343138000	usd
	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	303408000	usd
CY2022Q2	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	101514000	usd
CY2021Q2	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	94862000	usd
	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	195504000	usd
	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	183772000	usd
CY2022Q2	us-gaap	Interest Expense Debt InterestExpenseDebt	7252000	usd
CY2021Q2	us-gaap	Interest Expense Debt InterestExpenseDebt	7366000	usd
	us-gaap	Interest Expense Debt InterestExpenseDebt	14420000	usd
	us-gaap	Interest Expense Debt InterestExpenseDebt	14725000	usd
CY2022Q2	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	7899000	usd
CY2021Q2	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	9112000	usd
	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	18920000	usd
	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	18666000	usd
CY2022Q2	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	814914000	usd
CY2021Q2	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	687320000	usd
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	1591086000	usd
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	1355595000	usd
CY2022Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	49904000	usd
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	153198000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	119794000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	288830000	usd
CY2022Q2	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	9692000	usd
CY2021Q2	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	32017000	usd
	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	26870000	usd
	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	60441000	usd
CY2022Q2	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	692000	usd
CY2021Q2	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-702000	usd
	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-2926000	usd
	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-2764000	usd
CY2022Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10384000	usd
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	31315000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	23944000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	57677000	usd
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	39520000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	121883000	usd
	us-gaap	Net Income Loss NetIncomeLoss	95850000	usd
	us-gaap	Net Income Loss NetIncomeLoss	231153000	usd
CY2022Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2300000	usd
CY2021Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2300000	usd
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	4600000	usd
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	4753000	usd
CY2022Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	37220000	usd
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	119583000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	91250000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	226400000	usd
CY2022Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.62
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.99
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.51
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.77
CY2022Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.61
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.98
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.50
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.74
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	39520000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	121883000	usd
	us-gaap	Net Income Loss NetIncomeLoss	95850000	usd
	us-gaap	Net Income Loss NetIncomeLoss	231153000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-176093000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	28086000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-382941000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-53527000	usd
CY2022Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	-57427000	usd
CY2021Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	7888000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	-125857000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	-1055000	usd
CY2022Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	0	usd
CY2021Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	2000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	-1000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	4000	usd
CY2022Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	14354000	usd
CY2021Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	46000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	26987000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	523000	usd
CY2022Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	12261000	usd
CY2021Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	-1795000	usd
CY2022Q2	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	206905000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	29682000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	2153000	usd
CY2021Q2	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	-34223000	usd
	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	452128000	usd
	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	51910000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-330000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-548000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-659000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-1095000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-330000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-548000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-659000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1095000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-206575000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	34771000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-451469000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-50815000	usd
CY2022Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-167055000	usd
CY2021Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	156654000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-355619000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	180338000	usd
CY2022Q2	us-gaap	Stockholders Equity StockholdersEquity	2594090000	usd
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	2891367000	usd
CY2022Q2	us-gaap	Stockholders Equity StockholdersEquity	2594090000	usd
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	2891367000	usd
CY2022Q2	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	287.50
CY2021Q2	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	287.50
	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	575.00
	us-gaap	Preferred Stock Dividends Per Share Declared PreferredStockDividendsPerShareDeclared	594.17
CY2022Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.25
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.56
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.50
CY2022Q1	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2021Q1	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2021Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2022Q2	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2021Q2	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2022Q2	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2021Q2	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	8000	shares
CY2022Q1	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60335472	shares
CY2021Q1	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60023883	shares
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60184382	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	59905803	shares
CY2022Q2	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	5864	shares
CY2021Q2	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	5636	shares
	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	11505	shares
	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	12056	shares
CY2022Q2	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	72245	shares
CY2021Q2	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	77656	shares
	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	290687	shares
	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	326115	shares
CY2022Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	85059	shares
CY2021Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	86059	shares
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	52781	shares
CY2022Q2	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	788	shares
CY2021Q2	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	939	shares
	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	72781	shares
	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	84957	shares
CY2022Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60327734	shares
CY2021Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60106236	shares
CY2022Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60327734	shares
CY2021Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	60106236	shares
	us-gaap	Net Income Loss NetIncomeLoss	95850000	usd
	us-gaap	Net Income Loss NetIncomeLoss	231153000	usd
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	21998000	usd
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	27451000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	11886000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	10927000	usd
	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	12890000	usd
	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	34841000	usd
	sigi	Proceedsfromequityinvestmentsinexcessofcurrentyearearnings Proceedsfromequityinvestmentsinexcessofcurrentyearearnings	20252000	usd
	sigi	Proceedsfromequityinvestmentsinexcessofcurrentyearearnings Proceedsfromequityinvestmentsinexcessofcurrentyearearnings	1817000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-83232000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	15176000	usd
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	1000	usd
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-10000	usd
	sigi	Increase Decrease In Reserves For Losses And Loss Expenses Net Of Reinsurance Recoverables IncreaseDecreaseInReservesForLossesAndLossExpensesNetOfReinsuranceRecoverables	169114000	usd
	sigi	Increase Decrease In Reserves For Losses And Loss Expenses Net Of Reinsurance Recoverables IncreaseDecreaseInReservesForLossesAndLossExpensesNetOfReinsuranceRecoverables	167509000	usd
	sigi	Increase Decrease In Unearned Premiums Net Of Prepaid Reinsurance IncreaseDecreaseInUnearnedPremiumsNetOfPrepaidReinsurance	173817000	usd
	sigi	Increase Decrease In Unearned Premiums Net Of Prepaid Reinsurance IncreaseDecreaseInUnearnedPremiumsNetOfPrepaidReinsurance	165905000	usd
	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-17665000	usd
	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-9278000	usd
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	172231000	usd
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	151936000	usd
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	32464000	usd
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	34577000	usd
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	2116000	usd
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	1124000	usd
	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	-18530000	usd
	us-gaap	Increase Decrease In Employee Related Liabilities IncreaseDecreaseInEmployeeRelatedLiabilities	-11485000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	25598000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	21991000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-51171000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-31912000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	243483000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	292452000	usd
	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	5000000	usd
	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	11250000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1478298000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1158017000	usd
	sigi	Payments To Acquire Commercial Mortgage Loans PaymentsToAcquireCommercialMortgageLoans	-48926000	usd
	sigi	Payments To Acquire Commercial Mortgage Loans PaymentsToAcquireCommercialMortgageLoans	-25945000	usd
	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	18209000	usd
	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	76793000	usd
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	32179000	usd
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	40286000	usd
	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	2041614000	usd
	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	2596863000	usd
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	705039000	usd
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	307057000	usd
	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	7504000	usd
	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	217000	usd
	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	2200624000	usd
	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	2655450000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1684000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1032000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	392648000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	629512000	usd
	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	85162000	usd
	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	57316000	usd
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	2156000	usd
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	3128000	usd
	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	9013000	usd
	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	6245000	usd
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	14101000	usd
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9491000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-234497000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-258688000	usd
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	4600000	usd
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	4753000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32886000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	29155000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	12075000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	8916000	usd
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	4280000	usd
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	3790000	usd
	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	usd
	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	-479000	usd
	us-gaap	Proceeds From Debt Net Of Issuance Costs ProceedsFromDebtNetOfIssuanceCosts	35000000	usd
	us-gaap	Proceeds From Debt Net Of Issuance Costs ProceedsFromDebtNetOfIssuanceCosts	0	usd
	us-gaap	Repayments Of Debt RepaymentsOfDebt	35000000	usd
	us-gaap	Repayments Of Debt RepaymentsOfDebt	0	usd
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1202000	usd
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	229000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-46483000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-39742000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-37497000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-5978000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	45063000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	15231000	usd
CY2022Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	7566000	usd
CY2021Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	9253000	usd
	sigi	Interest Paid Operatingand Investing Activities InterestPaidOperatingandInvestingActivities	14240000	usd
	sigi	Interest Paid Operatingand Investing Activities InterestPaidOperatingandInvestingActivities	14547000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	40200000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	66000000	usd
	us-gaap	Operating Lease Payments OperatingLeasePayments	4086000	usd
	us-gaap	Operating Lease Payments OperatingLeasePayments	4348000	usd
	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	20000	usd
	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	4000	usd
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1202000	usd
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	229000	usd
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	41000	usd
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	183000	usd
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	5781000	usd
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	16000	usd
	us-gaap	Noncash Or Part Noncash Acquisition Fixed Assets Acquired1 NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1	17000	usd
	us-gaap	Noncash Or Part Noncash Acquisition Fixed Assets Acquired1 NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1	35000	usd
CY2022Q2	us-gaap	Cash Cash	401000	usd
CY2021Q4	us-gaap	Cash Cash	455000	usd
CY2022Q2	us-gaap	Restricted Cash RestrictedCash	7165000	usd
CY2021Q4	us-gaap	Restricted Cash RestrictedCash	44608000	usd
CY2022Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	7566000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	45063000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6833430000	usd
CY2021Q4	sigi	Maximumexposuretocreditconcentrationriskofthe Companysstockholdersequityotherthancertain U.S.Governmentagencies MaximumexposuretocreditconcentrationriskoftheCompanysstockholdersequityotherthancertainU.S.governmentagencies	0.10
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-50800000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	14345000	usd
CY2022Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	357697000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	6439278000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	6490753000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-9724000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	246301000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	17354000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	6709976000	usd
CY2022Q1	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-37599000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	9677000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Purchased With Credit Deterioration Increase DebtSecuritiesAvailableForSaleAllowanceForCreditLossPurchasedWithCreditDeteriorationIncrease	0	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	5842000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	-2213000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	-105000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-50800000	usd
CY2021Q1	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-8781000	usd
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	155000	usd
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-2427000	usd
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	-437000	usd
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	-61000	usd
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-6011000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-9724000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	31965000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Purchased With Credit Deterioration Increase DebtSecuritiesAvailableForSaleAllowanceForCreditLossPurchasedWithCreditDeteriorationIncrease	8318000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	5605000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	-3608000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	-1204000	usd
CY2022Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-50800000	usd
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-3969000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	3820000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-1102000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	-615000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery	-61000	usd
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	-6011000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	330440000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	6721000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	6817000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	2794530000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	5252000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	5218000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	2450184000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	20121000	usd
CY2022Q2	sigi	Maximumexposuretocreditconcentrationriskofthe Companysstockholdersequityotherthancertain U.S.Governmentagencies MaximumexposuretocreditconcentrationriskoftheCompanysstockholdersequityotherthancertainU.S.governmentagencies	0.10
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	19270000	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	864124000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	0	usd
CY2022Q2	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	0	usd
CY2022Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	6439278000	usd
CY2022Q2	us-gaap	Debt Securities Held To Maturity Amortized Cost After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss	32094000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	31305000	usd
CY2022Q2	us-gaap	Assets Held By Insurance Regulators AssetsHeldByInsuranceRegulators	23700000	usd
CY2022Q2	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	134400000	usd
CY2022Q2	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	5220000	usd
CY2021Q2	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	5469000	usd
	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	9337000	usd
	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	9096000	usd
CY2022Q2	us-gaap	Net Investment Income NetInvestmentIncome	70222000	usd
CY2021Q2	us-gaap	Net Investment Income NetInvestmentIncome	83731000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	142824000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	153447000	usd
CY2022Q2	sigi	Debt And Equity Securities Realized Gains DebtAndEquitySecuritiesRealizedGains	14552000	usd
CY2021Q2	sigi	Debt And Equity Securities Realized Gains DebtAndEquitySecuritiesRealizedGains	2079000	usd
	sigi	Debt And Equity Securities Realized Gains DebtAndEquitySecuritiesRealizedGains	16749000	usd
	sigi	Debt And Equity Securities Realized Gains DebtAndEquitySecuritiesRealizedGains	5755000	usd
CY2022Q2	sigi	Debt And Equity Securities Realized Losses DebtAndEquitySecuritiesRealizedLosses	19345000	usd
CY2021Q2	sigi	Debt And Equity Securities Realized Losses DebtAndEquitySecuritiesRealizedLosses	1811000	usd
	sigi	Debt And Equity Securities Realized Losses DebtAndEquitySecuritiesRealizedLosses	32905000	usd
	sigi	Debt And Equity Securities Realized Losses DebtAndEquitySecuritiesRealizedLosses	6282000	usd
CY2022Q2	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-4793000	usd
CY2021Q2	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	268000	usd
	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-16156000	usd
	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-527000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-21860000	usd
CY2021Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	7661000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-24014000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	18941000	usd
CY2022Q2	sigi	Losses On Investment Securities For Which We Have The Intent To Sell LossesOnInvestmentSecuritiesForWhichWeHaveTheIntentToSell	702000	usd
CY2021Q2	sigi	Losses On Investment Securities For Which We Have The Intent To Sell LossesOnInvestmentSecuritiesForWhichWeHaveTheIntentToSell	91000	usd
	sigi	Losses On Investment Securities For Which We Have The Intent To Sell LossesOnInvestmentSecuritiesForWhichWeHaveTheIntentToSell	5499000	usd
	sigi	Losses On Investment Securities For Which We Have The Intent To Sell LossesOnInvestmentSecuritiesForWhichWeHaveTheIntentToSell	453000	usd
CY2022Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-42880000	usd
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	10057000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-83232000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	15176000	usd
CY2022Q2	sigi	Change In Gain Loss On Investments ChangeInGainLossOnInvestments	-52900000	usd
	sigi	Change In Gain Loss On Investments ChangeInGainLossOnInvestments	-98400000	usd
CY2022Q2	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-13031000	usd
CY2021Q2	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	7458000	usd
	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-14843000	usd
	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	16942000	usd
CY2022Q2	sigi	Unrealized Gain Losson Equity Securities Sold UnrealizedGainLossonEquitySecuritiesSold	-8829000	usd
CY2021Q2	sigi	Unrealized Gain Losson Equity Securities Sold UnrealizedGainLossonEquitySecuritiesSold	203000	usd
	sigi	Unrealized Gain Losson Equity Securities Sold UnrealizedGainLossonEquitySecuritiesSold	-9171000	usd
	sigi	Unrealized Gain Losson Equity Securities Sold UnrealizedGainLossonEquitySecuritiesSold	1999000	usd
CY2022Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-21860000	usd
CY2021Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	7661000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-24014000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	18941000	usd
CY2022Q2	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	507753000	usd
CY2021Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	651071000	usd
CY2022Q2	us-gaap	Finance Lease Liability FinanceLeaseLiability	4289000	usd
CY2021Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	5450000	usd
CY2022Q2	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	505069000	usd
CY2021Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	506050000	usd
CY2022Q2	sigi	Net Asset Value NetAssetValue	97500000	usd
CY2021Q4	sigi	Net Asset Value NetAssetValue	83600000	usd
CY2022Q2	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	31305000	usd
CY2022Q2	sigi	Commercialmortgageloanfairvalue Commercialmortgageloanfairvalue	130044000	usd
CY2021Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	29460000	usd
CY2021Q4	sigi	Commercialmortgageloanfairvalue Commercialmortgageloanfairvalue	97598000	usd
CY2022Q1	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	14300000	usd
CY2021Q1	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	21000000	usd
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	13600000	usd
CY2020Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	21000000	usd
CY2022Q2	sigi	Change In Allowance For Credit Losses On Premiums Receivable ChangeInAllowanceForCreditLossesOnPremiumsReceivable	1500000	usd
	sigi	Change In Allowance For Credit Losses On Premiums Receivable ChangeInAllowanceForCreditLossesOnPremiumsReceivable	2700000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	573830000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	572230000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	601668000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	600068000	usd
CY2022Q1	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2021Q1	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1840000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1777000	usd
CY2022Q2	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	usd
CY2021Q2	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	-63000	usd
	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	usd
	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	usd
CY2022Q2	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
CY2021Q2	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
CY2022Q2	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
CY2021Q2	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
CY2022Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2021Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1777000	usd
CY2022Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1600000	usd
CY2021Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1777000	usd
	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"/><td style="width:67.613%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.384%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:13.958%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.384%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:13.961%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="9" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Six Months ended June 30,</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">($ in thousands)</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2022</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">2021</span></td></tr><tr><td colspan="3" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Gross reserve for loss and loss expense, at beginning of period</span></td><td colspan="3" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">4,580,903</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,260,355 </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of period</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">578,641</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">554,269 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ccffcc;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net reserve for loss and loss expense, at beginning of period</span></td><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">4,002,262</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3,706,086 </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Incurred loss and loss expense for claims occurring in the:</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%"> </span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td></tr><tr><td colspan="3" style="background-color:#ccffcc;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year</span></td><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">1,041,778</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ccffcc;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">886,801 </span></td><td style="background-color:#ccffcc;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior years</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(22,674)</span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(51,777)</span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ccffcc;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total incurred loss and loss expense</span></td><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">1,019,104</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">835,024 </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Paid loss and loss expense for claims occurring in the:</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%"> </span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td></tr><tr><td colspan="3" style="background-color:#ccffcc;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year</span></td><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">272,401</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ccffcc;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">227,505 </span></td><td style="background-color:#ccffcc;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior years</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">570,868</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">455,919 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ccffcc;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total paid loss and loss expense</span></td><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">843,269</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccffcc;padding:0 1pt"/><td colspan="2" style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">683,424 </span></td><td style="background-color:#ccffcc;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net reserve for loss and loss expense, at end of period</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">4,178,097</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3,857,686 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#d0ffd0;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Add: Reinsurance recoverable on unpaid loss and loss expense, at end of period</span></td><td colspan="3" style="background-color:#d0ffd0;padding:0 1pt"/><td colspan="2" style="background-color:#d0ffd0;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">544,082</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#d0ffd0;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#d0ffd0;padding:0 1pt"/><td colspan="2" style="background-color:#d0ffd0;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">579,567 </span></td><td style="background-color:#d0ffd0;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Gross reserve for loss and loss expense at end of period</span></td><td colspan="3" style="padding:0 1pt"/><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">4,722,179</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="padding:0 1pt"/><td colspan="2" style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,437,253 </span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table>
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4580903000	usd
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4260355000	usd
CY2021Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	578641000	usd
CY2020Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	554269000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	4002262000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	3706086000	usd
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	1041778000	usd
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	886801000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1019104000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	835024000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	272401000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	227505000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	570868000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	455919000	usd
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	843269000	usd
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	683424000	usd
CY2022Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	4178097000	usd
CY2021Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	3857686000	usd
CY2022Q2	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	544082000	usd
CY2021Q2	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	579567000	usd
CY2022Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4722179000	usd
CY2021Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4437253000	usd
	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	4
CY2022Q2	us-gaap	Net Investment Income NetInvestmentIncome	70222000	usd
CY2021Q2	us-gaap	Net Investment Income NetInvestmentIncome	83731000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	142824000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	153447000	usd
CY2022Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-42880000	usd
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	10057000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-83232000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	15176000	usd
CY2022Q2	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	27342000	usd
	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	168623000	usd
CY2021Q2	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	93788000	usd
	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	59592000	usd
CY2022Q2	us-gaap	Revenues Revenues	864818000	usd
CY2021Q2	us-gaap	Revenues Revenues	840518000	usd
	us-gaap	Revenues Revenues	1710880000	usd
	us-gaap	Revenues Revenues	1644425000	usd
CY2022Q2	us-gaap	Net Investment Income NetInvestmentIncome	70222000	usd
CY2021Q2	us-gaap	Net Investment Income NetInvestmentIncome	83731000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	142824000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	153447000	usd
CY2022Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-42880000	usd
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	10057000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-83232000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	15176000	usd
CY2022Q2	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	27342000	usd
CY2021Q2	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	93788000	usd
	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	59592000	usd
	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	168623000	usd
CY2022Q2	sigi	Taxoninvestmentincome Taxoninvestmentincome	4559000	usd
CY2021Q2	sigi	Taxoninvestmentincome Taxoninvestmentincome	18402000	usd
	sigi	Taxoninvestmentincome Taxoninvestmentincome	10172000	usd
	sigi	Taxoninvestmentincome Taxoninvestmentincome	32850000	usd
CY2022Q2	sigi	Totalinvestmentsegmentincomeafterfederalincometax Totalinvestmentsegmentincomeafterfederalincometax	22783000	usd
CY2021Q2	sigi	Totalinvestmentsegmentincomeafterfederalincometax Totalinvestmentsegmentincomeafterfederalincometax	75386000	usd
	sigi	Totalinvestmentsegmentincomeafterfederalincometax Totalinvestmentsegmentincomeafterfederalincometax	49420000	usd
	sigi	Totalinvestmentsegmentincomeafterfederalincometax Totalinvestmentsegmentincomeafterfederalincometax	135773000	usd
CY2022Q2	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	27342000	usd
CY2021Q2	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	93788000	usd
	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	59592000	usd
	sigi	Total Investmentsrevenue TotalInvestmentsrevenue	168623000	usd
CY2022Q2	us-gaap	Interest Expense Debt InterestExpenseDebt	7252000	usd
CY2021Q2	us-gaap	Interest Expense Debt InterestExpenseDebt	7366000	usd
	us-gaap	Interest Expense Debt InterestExpenseDebt	14420000	usd
	us-gaap	Interest Expense Debt InterestExpenseDebt	14725000	usd
CY2022Q2	us-gaap	Other General Expense OtherGeneralExpense	7899000	usd
CY2021Q2	us-gaap	Other General Expense OtherGeneralExpense	9112000	usd
	us-gaap	Other General Expense OtherGeneralExpense	18920000	usd
	us-gaap	Other General Expense OtherGeneralExpense	18666000	usd
CY2022Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	49904000	usd
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	153198000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	119794000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	288830000	usd
CY2022Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2300000	usd
CY2021Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2300000	usd
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	4600000	usd
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	4753000	usd
CY2022Q2	sigi	Income Available To Common Stockholders Before Federal Income Tax IncomeAvailableToCommonStockholdersBeforeFederalIncomeTax	47604000	usd
CY2021Q2	sigi	Income Available To Common Stockholders Before Federal Income Tax IncomeAvailableToCommonStockholdersBeforeFederalIncomeTax	150898000	usd
	sigi	Income Available To Common Stockholders Before Federal Income Tax IncomeAvailableToCommonStockholdersBeforeFederalIncomeTax	115194000	usd
	sigi	Income Available To Common Stockholders Before Federal Income Tax IncomeAvailableToCommonStockholdersBeforeFederalIncomeTax	284077000	usd
CY2022Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	49904000	usd
CY2022Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10384000	usd
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	39520000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-222903000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-46810000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-176093000	usd
CY2022Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Gross NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeGross	-72691000	usd
CY2022Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Tax NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeTax	-15264000	usd
CY2022Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	-57427000	usd
CY2022Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Before Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleBeforeTax	0	usd
CY2022Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleTax	0	usd
CY2022Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	0	usd
CY2022Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securitiesbefore Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesbeforeTax	18170000	usd
CY2022Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesTax	3816000	usd
CY2022Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	14354000	usd
CY2022Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Gross DebtSecuritiesAvailableforsaleAllowanceforCreditLossGross	15519000	usd
CY2022Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Tax DebtSecuritiesAvailableforsaleAllowanceforCreditLossTax	3258000	usd
CY2022Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	12261000	usd
CY2022Q2	sigi	Total Unrealized Gains Losses On Investment Securities Gross TotalUnrealizedGainsLossesOnInvestmentSecuritiesGross	-261905000	usd
CY2022Q2	sigi	Total Unrealized Gains Losses On Investment Securities Tax TotalUnrealizedGainsLossesOnInvestmentSecuritiesTax	-55000000	usd
CY2022Q2	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	206905000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-417000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-87000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-330000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-417000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-87000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-330000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-261488000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-54913000	usd
CY2022Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-206575000	usd
CY2022Q2	sigi	Comprehensive Income Loss Before Tax ComprehensiveIncomeLossBeforeTax	-211584000	usd
CY2022Q2	sigi	Comprehensive Income Loss Tax ComprehensiveIncomeLossTax	-44529000	usd
CY2022Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-167055000	usd
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	153198000	usd
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	31315000	usd
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	121883000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	35553000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	7467000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	28086000	usd
CY2021Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Gross NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeGross	9985000	usd
CY2021Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Tax NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeTax	2097000	usd
CY2021Q2	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	7888000	usd
CY2021Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Before Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleBeforeTax	3000	usd
CY2021Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleTax	1000	usd
CY2021Q2	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	2000	usd
CY2021Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securitiesbefore Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesbeforeTax	58000	usd
CY2021Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesTax	12000	usd
CY2021Q2	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	46000	usd
CY2021Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Gross DebtSecuritiesAvailableforsaleAllowanceforCreditLossGross	-2272000	usd
CY2021Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Tax DebtSecuritiesAvailableforsaleAllowanceforCreditLossTax	-477000	usd
CY2021Q2	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	-1795000	usd
CY2021Q2	sigi	Total Unrealized Gains Losses On Investment Securities Gross TotalUnrealizedGainsLossesOnInvestmentSecuritiesGross	43321000	usd
CY2021Q2	sigi	Total Unrealized Gains Losses On Investment Securities Tax TotalUnrealizedGainsLossesOnInvestmentSecuritiesTax	9098000	usd
CY2021Q2	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	-34223000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-693000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-145000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-548000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-693000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-145000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-548000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	44014000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	9243000	usd
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	34771000	usd
CY2021Q2	sigi	Comprehensive Income Loss Before Tax ComprehensiveIncomeLossBeforeTax	197212000	usd
CY2021Q2	sigi	Comprehensive Income Loss Tax ComprehensiveIncomeLossTax	40558000	usd
CY2021Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	156654000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	119794000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	23944000	usd
	us-gaap	Net Income Loss NetIncomeLoss	95850000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-484735000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-101794000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-382941000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Gross NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeGross	-159312000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Tax NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeTax	-33455000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	-125857000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Before Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleBeforeTax	-1000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleTax	0	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	-1000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securitiesbefore Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesbeforeTax	34161000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesTax	7174000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	26987000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Gross DebtSecuritiesAvailableforsaleAllowanceforCreditLossGross	37571000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Tax DebtSecuritiesAvailableforsaleAllowanceforCreditLossTax	7889000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	29682000	usd
	sigi	Total Unrealized Gains Losses On Investment Securities Gross TotalUnrealizedGainsLossesOnInvestmentSecuritiesGross	-572314000	usd
	sigi	Total Unrealized Gains Losses On Investment Securities Tax TotalUnrealizedGainsLossesOnInvestmentSecuritiesTax	-120186000	usd
	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	452128000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-834000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-175000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-659000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-834000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-175000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-659000	usd
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-571480000	usd
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-120011000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-451469000	usd
	sigi	Comprehensive Income Loss Before Tax ComprehensiveIncomeLossBeforeTax	-451686000	usd
	sigi	Comprehensive Income Loss Tax ComprehensiveIncomeLossTax	-96067000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-355619000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	288830000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	57677000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-14228000	usd
	us-gaap	Net Income Loss NetIncomeLoss	231153000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-67755000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-53527000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Gross NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeGross	-1335000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income Tax NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncomeTax	-280000	usd
	sigi	Non Credit Portionof Other Than Temporary Impairments Recognizedin Other Comprehensive Income NonCreditPortionofOtherThanTemporaryImpairmentsRecognizedinOtherComprehensiveIncome	-1055000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Before Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleBeforeTax	5000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleTax	1000	usd
	sigi	Amortization Of Net Unrealized Gains Losses On Held To Maturity Transferred From Available For Sale Netof Tax AmortizationOfNetUnrealizedGainsLossesOnHeldToMaturityTransferredFromAvailableForSaleNetofTax	4000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securitiesbefore Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesbeforeTax	662000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesTax	139000	usd
	sigi	Oci Reclassification Adjustmentfrom Aoc Ifor Writedownof Securities Netof Tax OCIReclassificationAdjustmentfromAOCIforWritedownofSecuritiesNetofTax	523000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Gross DebtSecuritiesAvailableforsaleAllowanceforCreditLossGross	2725000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Tax DebtSecuritiesAvailableforsaleAllowanceforCreditLossTax	572000	usd
	sigi	Debt Securities Availableforsale Allowancefor Credit Loss Net DebtSecuritiesAvailableforsaleAllowanceforCreditLossNet	2153000	usd
	sigi	Total Unrealized Gains Losses On Investment Securities Gross TotalUnrealizedGainsLossesOnInvestmentSecuritiesGross	-65708000	usd
	sigi	Total Unrealized Gains Losses On Investment Securities Tax TotalUnrealizedGainsLossesOnInvestmentSecuritiesTax	-13798000	usd
	sigi	Total Unrealized Gains Losseson Investment Securities TotalUnrealizedGainsLossesonInvestmentSecurities	51910000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-1386000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-291000	usd
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-1095000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-1386000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-291000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1095000	usd
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-64322000	usd
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-13507000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-50815000	usd
	sigi	Comprehensive Income Loss Before Tax ComprehensiveIncomeLossBeforeTax	224508000	usd
	sigi	Comprehensive Income Loss Tax ComprehensiveIncomeLossTax	44170000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	180338000	usd
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-659000	usd
CY2020Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	100000000	usd
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	86059	shares
CY2022Q2	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	85059	shares
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	6500000	usd
CY2022Q2	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	90100000	usd
CY2022Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	37220000	usd
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	119583000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	91250000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	226400000	usd
CY2022Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	60440000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	60164000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	60412000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	60126000	shares
CY2022Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	407000	shares
CY2021Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	330000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	416000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	352000	shares
CY2022Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	60847000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	60494000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	60828000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	60478000	shares
CY2022Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.62
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.99
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.51
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.77
CY2022Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.61
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.98
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.50
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.74

Files In Submission

Name	View Source	Status
0000230557-22-000019-index-headers.html	Edgar Link	pending
0000230557-22-000019-index.html	Edgar Link	pending
0000230557-22-000019.txt	Edgar Link	pending
0000230557-22-000019-xbrl.zip	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
R14.htm	Edgar Link	pending
R15.htm	Edgar Link	pending
R16.htm	Edgar Link	pending
R17.htm	Edgar Link	pending
R18.htm	Edgar Link	pending
R19.htm	Edgar Link	pending
R2.htm	Edgar Link	pending
R20.htm	Edgar Link	pending
R21.htm	Edgar Link	pending
R22.htm	Edgar Link	pending
R23.htm	Edgar Link	pending
R24.htm	Edgar Link	pending
R25.htm	Edgar Link	pending
R26.htm	Edgar Link	pending
R27.htm	Edgar Link	pending
R28.htm	Edgar Link	pending
R29.htm	Edgar Link	pending
R3.htm	Edgar Link	pending
R30.htm	Edgar Link	pending
R31.htm	Edgar Link	pending
R32.htm	Edgar Link	pending
R33.htm	Edgar Link	pending
R34.htm	Edgar Link	pending
R35.htm	Edgar Link	pending
R36.htm	Edgar Link	pending
R37.htm	Edgar Link	pending
R38.htm	Edgar Link	pending
R39.htm	Edgar Link	pending
R4.htm	Edgar Link	pending
R40.htm	Edgar Link	pending
R41.htm	Edgar Link	pending
R42.htm	Edgar Link	pending
R43.htm	Edgar Link	pending
R44.htm	Edgar Link	pending
R45.htm	Edgar Link	pending
R46.htm	Edgar Link	pending
R47.htm	Edgar Link	pending
R48.htm	Edgar Link	pending
R49.htm	Edgar Link	pending
R5.htm	Edgar Link	pending
R50.htm	Edgar Link	pending
R51.htm	Edgar Link	pending
R52.htm	Edgar Link	pending
R53.htm	Edgar Link	pending
R54.htm	Edgar Link	pending
R55.htm	Edgar Link	pending
R56.htm	Edgar Link	pending
R57.htm	Edgar Link	pending
R58.htm	Edgar Link	pending
R59.htm	Edgar Link	pending
R6.htm	Edgar Link	pending
R60.htm	Edgar Link	pending
R61.htm	Edgar Link	pending
R62.htm	Edgar Link	pending
R63.htm	Edgar Link	pending
R64.htm	Edgar Link	pending
R65.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending
sigi-20220630.htm	Edgar Link	pending
sigi-20220630.xsd	Edgar Link	pending
sigi-20220630_cal.xml	Edgar Link	unprocessable
sigi-20220630_def.xml	Edgar Link	unprocessable
sigi-20220630_htm.xml	Edgar Link	completed
sigi-20220630_lab.xml	Edgar Link	unprocessable
sigi-20220630_pre.xml	Edgar Link	unprocessable
sigi-ex311_6302022xq2.htm	Edgar Link	pending
sigi-ex312_6302022xq2.htm	Edgar Link	pending
sigi-ex321_6302022xq2.htm	Edgar Link	pending
sigi-ex322_6302022xq2.htm	Edgar Link	pending

Create your account

Find Stocks Worth Researching

Deeply Understand Businesses

Value Businesses Intelligently

$SIGI
Selective Insurance Group Inc Stock $sigi

2022 Q3 Form 10-Q Financial Statement

#000023055722000019 Filed on August 04, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SIGI Selective Insurance Group Inc Stock $sigi

2022 Q3 Form 10-Q Financial Statement

#000023055722000019 Filed on August 04, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SIGI
Selective Insurance Group Inc Stock $sigi