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v3.21.2

Segment Information - Summary of Premiums Written and Earned by Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |
Net | $ 926,820 | $ 811,898 | $ 1,842,741 | $ 1,734,471
Direct | 972,900 | 828,800 | 1,926,300 | 1,786,700
Private Passenger Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 650,800 | 579,700 | 1,304,600 | 1,273,600
Direct | 646,000 | 555,000 | 1,312,500 | 1,265,400
Homeowners Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 169,400 | 146,500 | 330,200 | 286,000
Direct | 207,900 | 180,700 | 378,100 | 328,200
Commercial Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 64,600 | 51,100 | 127,200 | 106,300
Direct | 66,200 | 55,800 | 135,100 | 117,500
Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 42,000 | 34,600 | 80,700 | 68,600
Direct | 52,800 | 37,300 | 100,600 | 75,600
Property and Casualty Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 919,515 | 804,797 | 1,828,330 | 1,720,140
Direct | 963,418 | 823,031 | 1,910,024 | 1,772,775
Property and Casualty Lines [Member] | Private Passenger Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 650,800 | 579,700 | 1,304,600 | 1,273,600
Direct | 646,000 | 555,000 | 1,312,500 | 1,265,400
Property and Casualty Lines [Member] | Homeowners Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 169,400 | 146,500 | 330,200 | 286,000
Direct | 207,900 | 180,700 | 378,100 | 328,200
Property and Casualty Lines [Member] | Commercial Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 64,600 | 51,100 | 127,200 | 106,300
Direct | 66,200 | 55,800 | 135,100 | 117,500
Property and Casualty Lines [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 34,700 | 27,500 | 66,300 | 54,200
Direct | 43,300 | 31,500 | 84,300 | 61,700
Other Segments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 7,300 | 7,100 | 14,400 | 14,400
Direct | 9,500 | 5,800 | 16,300 | 13,900
Other Segments [Member] | Private Passenger Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 0 | 0 | 0 | 0
Direct | 0 | 0 | 0 | 0
Other Segments [Member] | Homeowners Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 0 | 0 | 0 | 0
Direct | 0 | 0 | 0 | 0
Other Segments [Member] | Commercial Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 0 | 0 | 0 | 0
Direct | 0 | 0 | 0 | 0
Other Segments [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net | 7,300 | 7,100 | 14,400 | 14,400
Direct | $ 9,500 | $ 5,800 | $ 16,300 | $ 13,900

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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 http://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 http://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 http://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 http://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 http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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