Reinsurance - Variable Interest Entity (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Effects of Reinsurance [Line Items]
Assets	$ 7,511,309	$ 7,354,526
Home Re 2018-1
Effects of Reinsurance [Line Items]
Assets	218,343	218,343
Home Re 2019-1
Effects of Reinsurance [Line Items]
Assets	208,146	208,146
Home Re 2020-1
Effects of Reinsurance [Line Items]
Assets	312,199	$ 412,917
Home Re 2021-1
Effects of Reinsurance [Line Items]
Assets	398,848
Home Re 2021-2
Effects of Reinsurance [Line Items]
Assets	$ 398,429

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details