Commercial mortgage loans, Percentage

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Line items represent reporting 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.

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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-Publisher FASB
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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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The cash inflow associated with the sale of loans receivables arising from the financing of goods and services.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount of restructured debt contingently payable based on the occurrence of future events or circumstances.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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Investments (Narrative) (Details) - USD ($)	3 Months Ended
Investments (Narrative) (Details) - USD ($)	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investment [Line Items]
Securities sold under agreements to repurchase	$ 0		$ 0
Commercial mortgage loans, Percentage	100.00%		100.00%
Commercial mortgage and other loans, Acquired	$ 0	$ 0
Commercial mortgage and other loans, Sold	0	0
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0	0
Troubled debt restructuring, Commitment to borrowers	0		$ 0
Corporate securities
Investment [Line Items]
Gross unrealized losses of twelve months or more concentrated in various sectors	$ 23,300,000		16,200,000
California
Investment [Line Items]
Commercial mortgage loans, Percentage	23.00%
Texas
Investment [Line Items]
Commercial mortgage loans, Percentage	14.00%
New York
Investment [Line Items]
Commercial mortgage loans, Percentage	6.00%
Europe
Investment [Line Items]
Commercial mortgage loans, Percentage	5.00%
Australia
Investment [Line Items]
Commercial mortgage loans, Percentage	4.00%
Mexico
Investment [Line Items]
Commercial mortgage loans, Percentage	2.00%
Fixed maturities
Investment [Line Items]
Gross unrealized losses	$ 51,477,000		18,842,000
Gross unrealized losses of twelve months or more concentrated in various sectors	23,341,000		16,170,000
Fixed maturities \| NAIC high or highest quality rating
Investment [Line Items]
Gross unrealized losses	44,700,000		13,900,000
Fixed maturities \| NAIC other than high or highest quality rating
Investment [Line Items]
Gross unrealized losses	6,800,000		$ 4,900,000
Other Income \| Equity securities
Investment [Line Items]
Unrealized Gain (Loss) on Investments	$ (1,200,000)	$ 1,400,000