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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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Other Assets (Details) $ in Thousands	3 Months Ended	12 Months Ended
Other Assets (Details) $ in Thousands	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) Reportingunit	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Goodwill [Line Items]
Goodwill, impairment loss		$ 132,128	$ 0	$ 0
Goodwill, impairment loss		$ 0
Accumulated Impairment Losses [Member] \| Natural Disasters and Other Casualty Events [Member]
Goodwill [Line Items]
Goodwill, impairment loss	$ 132,200
Accumulated Impairment Losses [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Natural Disasters and Other Casualty Events [Member]
Goodwill [Line Items]
Number of reporting units \| Reportingunit		269
Fair Value lower than carrying value \| Reportingunit		87