Board of Directors, Number of Directors

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- Definition

Board of Directors, Number of Directors Appointed

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 3
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- Definition

Amount of funds held as security for payments to be received under reinsurance contracts.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount of cash outflow to acquire investments classified as other.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 13
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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, policy benefits and policy reserves. Excludes premiums paid under reinsurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 944
-SubTopic 310
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-Paragraph 6
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Transactions With Related Parties (Details) $ in Thousands	3 Months Ended		12 Months Ended
Transactions With Related Parties (Details) $ in Thousands	Mar. 31, 2020 USD ($) director	Mar. 31, 2019 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Purchases of other investments	$ 228,471	$ 324,593
Reinsurance recoverable on unpaid and paid losses and LAE	$ 4,303,135			$ 4,346,816
Premia Holdings Ltd.
Related Party Transaction [Line Items]
Percentage ownership			25.00%
Number of directors appointed by Arch to the Board \| director	2
Number of directors on the Board \| director	7
Purchases of other investments			$ 100,000
Reinsurance recoverable on unpaid and paid losses and LAE	$ 216,000			177,700
Funds held liability	$ 210,200			$ 180,000