Investments Allowance for Mortgage Loan Losses (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses
Allowance for Loan and Lease Losses, Write-offs	$ (0.3)	$ 0.0
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable, Allowance	0.0	0.0	$ 0.2	$ 0.0
Provision for Loan and Lease Losses	$ 0.1	$ 0.0

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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Amount of expense related to estimated loss from loan and lease transactions.

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