Goodwill and Intangible Assets, net - Goodwill Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2019	Sep. 30, 2019
Goodwill [Roll Forward]
Beginning balance		$ 47,396
Impairment		(28,025)
Acquisitions		29,373
Ending balance		48,744
Property and Casualty
Goodwill [Roll Forward]
Beginning balance		9,460
Impairment		0
Acquisitions		0
Ending balance		9,460
Supplemental
Goodwill [Roll Forward]
Beginning balance		0
Impairment		0
Acquisitions		19,286
Ending balance		19,286
Retirement
Goodwill [Roll Forward]
Beginning balance		28,025
Impairment	$ (28,025)	(28,025)
Acquisitions		10,087
Ending balance		10,087
Life
Goodwill [Roll Forward]
Beginning balance		9,911
Impairment		0
Acquisitions		0
Ending balance		$ 9,911

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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