New Accounting Standards	9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
New Accounting Standards	New Accounting Standards — We did not adopt any new accounting standards during the nine months ended September 30, 2021. We assessed the adoption impacts of recently issued accounting standards by the Financial Accounting Standards Board on our consolidated financial statements as well as material updates to previous assessments, if any, from our Annual Report on Form 10-K for the fiscal year ended December 31, 2020. There were no new material accounting standards issued in the nine months ended September 30, 2021, that impacted The Progressive Corporation.

The entire disclosure for all significant accounting policies of the reporting entity.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=123372394&loc=d3e18726-107790

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-URI http://asc.fasb.org/topic&trid=2122369

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