Name:	pgr_FairValueInputsMarketCapPriceChangePercentageRangeMaximum
Namespace Prefix:	pgr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Weighted average market capitalization percentage used to calculate the periodic increase/(decrease) in valuation of Level 3 securities. This value represents the minimum change in the range of valuation changes for the period.

No definition available.

Name:	pgr_FairValueInputsMarketCapPriceChangePercentageRangeMinimum
Namespace Prefix:	pgr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Weighted average market capitalization percentage used to calculate the periodic increase/(decrease) in valuation of Level 3 securities. This value represents the weighted average change for the period.

No definition available.

Name:	pgr_FairValueInputsMarketCapPriceChangePercentageWeightedAverage
Namespace Prefix:	pgr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

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

No definition available.

Name:	us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
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 https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentSecondaryCategorizationAxis=pgr_TotalQuantitativeLevelThreeSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InvestmentSecondaryCategorizationAxis=pgr_ThirdPartyPricingExemptionSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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