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Limited partnership financial reporting lag time, months.

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- Definition

Percentage threshold that triggers a review of available for sale debt securities for declines in market value.

+ References

No definition available.

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- Definition

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.

+ References

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-Publisher FASB
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- Definition

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

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

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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 less than twelve months.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

This element represents the excess of the cost (face amount, notional amount) of an investment (security, contract) over its fair value which deficiency has not been recognized in earnings of the entity.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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-Glossary Investing Activities
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Line items represent financial 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.

+ References

No definition available.

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Investments (Narrative) (Details) - USD ($) $ in Thousands		6 Months Ended		12 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Thousands	Aug. 24, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold that triggers a review of available for sale debt securities for declines in market value		80.00%
Aggregate market value of investments in unrealized loss position		$ 2,129,518		$ 2,510,133
Gross unrealized losses on investments in unrealized loss position		49,911		66,508
Other invested assets		774,646		613,740
Gross unrealized depreciation		$ 0		$ 0
Sales Revenue, Net [Member]
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold of unrealized losses not exceeded by any one single issuer		5.00%	5.00%	1.00%
Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Limited partnership financial reporting lag time, months		1 month
Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Limited partnership financial reporting lag time, months		3 months
Heartland Corp [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sale of business	$ 49,000
Investment Grade [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation		$ 23,626		$ 36,646
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation		17,428
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Aggregate market value of investments in unrealized loss position		2,129,518		2,510,133
Gross unrealized losses on investments in unrealized loss position		49,911		66,508
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation		29,271		40,537
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation		$ 20,640		25,971
Fixed Maturity Securities [Member] \| Sales Revenue, Net [Member]
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold of unrealized losses not exceeded by any one single issuer		5.00%
Foreign Exchange Losses [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation				22,882
Limited Partnerships [Member]
Schedule of Available-for-sale Securities [Line Items]
Additional contractual commitments		$ 364,196
Other invested assets		$ 142,964		$ 57,126