Assets Deposited With Governmental Authorities.

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Commercial mortgage loans, Percentage

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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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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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

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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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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 ($) $ in Thousands	12 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Fixed maturities, available for sale	$ 5,681,970	$ 5,199,595
Securities sold under agreements to repurchase	0	0
Fair value of collateral	$ 0	$ 143,000
Commercial mortgage loans, Percentage	100.00%	100.00%
Assets Deposited With Governmental Authorities	$ 3,800	$ 3,700
Commercial mortgage and other loans, acquired	0	3,000
Commercial mortgage and other loans, sold	5,000	0
Fixed Maturities
Investment [Line Items]
Fixed maturities, available for sale	5,681,970	5,199,595
Gross Unrealized Losses	23,843	142,065
Gross unrealized losses of twelve months or more concentrated in various sectors	20,712	60,301
Fixed Maturities \| NAIC High or Highest Quality Rating
Investment [Line Items]
Gross Unrealized Losses	16,000	121,300
Fixed Maturities \| NAIC Other Than High or Highest Quality Rating
Investment [Line Items]
Gross Unrealized Losses	7,800	20,800
Fixed Maturities
Investment [Line Items]
Gross unrealized losses of twelve months or more concentrated in various sectors	20,700	60,300
Other Income (Loss) \| Equity securities
Investment [Line Items]
Unrealized Gain (Loss) on Investments	(1,000)	$ (2,800)
Other Comprehensive Income (Loss) \| Equity securities
Investment [Line Items]
Unrealized Gain (Loss) on Investments			$ 2,000
Carrying value of non-income producing assets
Investment [Line Items]
Fixed maturities, available for sale	$ 8,400
California
Investment [Line Items]
Commercial mortgage loans, Percentage	19.00%
Texas
Investment [Line Items]
Commercial mortgage loans, Percentage	14.00%
New York
Investment [Line Items]
Commercial mortgage loans, Percentage	7.00%
Europe
Investment [Line Items]
Commercial mortgage loans, Percentage	9.00%
Mexico
Investment [Line Items]
Commercial mortgage loans, Percentage	2.00%
Australia
Investment [Line Items]
Commercial mortgage loans, Percentage	2.00%