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v3.20.2

Segment Information - Summary of Premiums Written and Earned by Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | $ 811,898 | $ 888,776 | $ 1,734,471 | $ 1,759,021
Direct Premiums Written | 828,800 | 946,100 | 1,786,700 | 1,868,200
Private Passenger Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 579,700 | 684,300 | 1,273,600 | 1,356,900
Direct Premiums Written | 555,000 | 697,600 | 1,265,400 | 1,402,900
Homeowners Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 146,500 | 123,900 | 286,000 | 243,200
Direct Premiums Written | 180,700 | 159,000 | 328,200 | 289,900
Commercial Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 51,100 | 51,400 | 106,300 | 101,000
Direct Premiums Written | 55,800 | 55,800 | 117,500 | 110,200
Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 34,600 | 29,200 | 68,600 | 57,900
Direct Premiums Written | 37,300 | 33,700 | 75,600 | 65,200
Property and Casualty Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 804,800 | 881,800 | 1,720,200 | 1,744,900
Direct Premiums Written | 823,100 | 938,100 | 1,772,800 | 1,853,400
Property and Casualty Lines [Member] | Private Passenger Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 579,700 | 684,300 | 1,273,600 | 1,356,900
Direct Premiums Written | 555,000 | 697,600 | 1,265,400 | 1,402,900
Property and Casualty Lines [Member] | Homeowners Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 146,500 | 123,900 | 286,000 | 243,200
Direct Premiums Written | 180,700 | 159,000 | 328,200 | 289,900
Property and Casualty Lines [Member] | Commercial Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 51,100 | 51,400 | 106,300 | 101,000
Direct Premiums Written | 55,800 | 55,800 | 117,500 | 110,200
Property and Casualty Lines [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 27,500 | 22,200 | 54,300 | 43,800
Direct Premiums Written | 31,600 | 25,700 | 61,700 | 50,400
Other Segments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 7,100 | 7,000 | 14,300 | 14,100
Direct Premiums Written | 5,700 | 8,000 | 13,900 | 14,800
Other Segments [Member] | Private Passenger Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Direct Premiums Written | 0 | 0 | 0 | 0
Other Segments [Member] | Homeowners Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Direct Premiums Written | 0 | 0 | 0 | 0
Other Segments [Member] | Commercial Automobile Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Direct Premiums Written | 0 | 0 | 0 | 0
Other Segments [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 7,100 | 7,000 | 14,300 | 14,100
Direct Premiums Written | $ 5,700 | $ 8,000 | $ 13,900 | $ 14,800

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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=116637232&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=34713774&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=116637391&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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