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v3.22.2

Segment Information - Summary of Premiums Written and Earned by Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | $ 987,512 | $ 926,820 | $ 1,950,062 | $ 1,842,741
Direct premiums written | 1,034,100 | 972,900 | 2,052,300 | 1,926,300
Private passenger automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 666,000 | 650,800 | 1,325,300 | 1,304,600
Direct premiums written | 653,800 | 646,000 | 1,335,000 | 1,312,500
Homeowners |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 205,900 | 169,400 | 397,900 | 330,200
Direct premiums written | 251,800 | 207,900 | 462,100 | 378,100
Commercial automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 66,100 | 64,600 | 130,600 | 127,200
Direct premiums written | 69,800 | 66,200 | 141,400 | 135,100
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 49,500 | 42,000 | 96,300 | 80,700
Direct premiums written | 58,700 | 52,800 | 113,800 | 100,600
Property & Casualty |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 980,304 | 919,515 | 1,935,722 | 1,828,330
Direct premiums written | 1,025,749 | 963,418 | 2,037,134 | 1,910,024
Property & Casualty | Private passenger automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 666,000 | 650,800 | 1,325,300 | 1,304,600
Direct premiums written | 653,800 | 646,000 | 1,335,000 | 1,312,500
Property & Casualty | Homeowners |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 205,900 | 169,400 | 397,900 | 330,200
Direct premiums written | 251,800 | 207,900 | 462,100 | 378,100
Property & Casualty | Commercial automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 66,100 | 64,600 | 130,600 | 127,200
Direct premiums written | 69,800 | 66,200 | 141,400 | 135,100
Property & Casualty | Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 42,300 | 34,700 | 81,900 | 66,300
Direct premiums written | 50,300 | 43,300 | 98,600 | 84,300
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 7,200 | 7,300 | 14,400 | 14,400
Direct premiums written | 8,400 | 9,500 | 15,200 | 16,300
Other | Private passenger automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Direct premiums written | 0 | 0 |  | 0
Other | Homeowners |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Direct premiums written | 0 | 0 |  | 0
Other | Commercial automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Direct premiums written | 0 | 0 |  | 0
Other | Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 7,200 | 7,300 | 14,400 | 14,400
Direct premiums written | $ 8,400 | $ 9,500 | $ 15,200 | $ 16,300

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- Definition Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column E)) -URI https://asc.fasb.org/extlink&oid=120401096&loc=d3e574992-122915 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(c)) -URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI https://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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