Subsequent Events (Details) - USD ($) $ in Millions	1 Months Ended
	Oct. 31, 2019	Nov. 08, 2019	Sep. 30, 2019
Subsequent Event | Variable Interest Entity, Not Primary Beneficiary | Bellemeade Re 2019-4 Ltd.
Bellemeade 2019-3 Ltd.
Aggregate excess of loss reinsurance agreement	$ 577.3
Aggregate losses	$ 162.4
Agreement period	10 years
SPV issuance of insurance-linked notes	$ 577.3
Common shares
Bellemeade 2019-3 Ltd.
Remaining authorized repurchase amount			$ 160.9
Common shares | Subsequent Event
Bellemeade 2019-3 Ltd.
Authorized repurchase amount		$ 1,000.0