Name:	pgr_DebtSecuritiesAvailableforSalePercentOfTotalFairValue
Namespace Prefix:	pgr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Debt Securities, Available-for-sale, Accumulated Gross Realized Gain (Loss), before Tax

No definition available.

Name:	pgr_DebtSecuritiesAvailableforsaleAccumulatedGrossRealizedGainLossbeforeTax
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Equity Securities, FV-NI, Gross Realized Gains (Losses), before Tax

No definition available.

Name:	pgr_EquitySecuritiesFVNIGrossRealizedGainsLossesbeforeTax
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Pre-tax accumulated gross unrealized gains of equity securities in the investment portfolio, reflecting the balance recorded in AOCI for periods prior to adoption of ASU 2016-01.

No definition available.

Name:	pgr_EquitySecuritiesFVNIGrossUnrealizedGainsbeforeTaxes
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Pre-tax accumulated gross unrealized losses of equity securities in the investment portfolio, reflecting the balance recorded in AOCI for periods prior to adoption of ASU 2016-01.

No definition available.

Name:	pgr_EquitySecuritiesFVNIGrossUnrealizedLossesbeforeTaxes
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of investment in equity securities measured at fair value with changes in fair value recognized in earnings (FV-NI), reflected as a percentage of the total investment portfolio fair value.

No definition available.

Name:	pgr_EquitySecuritiesFVNIPercentOfTotalFairValue
Namespace Prefix:	pgr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Pre-tax accumulated gross unrealized gain of total debt and equity financial instruments

No definition available.

Name:	pgr_InvestmentsAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Pre-tax accumulated gross unrealized loss of total debt and equity financial instruments

No definition available.

Name:	pgr_InvestmentsAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amortized cost of total debt and equity financial instruments

No definition available.

Name:	pgr_InvestmentsAmortizedCost
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Pre-tax accumulated net holding period gain/(loss) for hybrid fixed-maturity securities and FV-NI equity securities for which the net change in unrealized gain/(loss) recorded as a component of realized gain/(loss) on the Income Statement

No definition available.

Name:	pgr_InvestmentsGrossRealizedGainsLossesbeforeTax
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Securities held in the investment portfolio, reflected as a percentage of the total investment portfolio fair value.

No definition available.

Name:	pgr_InvestmentsPercentOfTotalFairValue
Namespace Prefix:	pgr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Securities held in the portfolio of a consolidated, non-insurance subsidiary of the holding company, net of any unsettled security transactions.

No definition available.

Name:	pgr_SecuritiesHeldInConsolidatedNonInsuranceSubsidiary
Namespace Prefix:	pgr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Name:	us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_EquitySecuritiesFVNIAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

Name:	us-gaap_EquitySecuritiesFvNi
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

No definition available.

Name:	us-gaap_EquitySecuritiesFvNiCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_InvestmentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

Name:	us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of other payables due to broker-dealers or clearing organizations.

No definition available.

Name:	us-gaap_OtherPayablesToBrokerDealersAndClearingOrganizations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_NonredeemablePreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InformationByCategoryOfDebtSecurityAxis=us-gaap_FixedMaturitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesSecuritizedLoansAndReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_RedeemablePreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: