Additional contractual commitments

No definition available.

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- Definition

Limited partnership financial reporting lag time, months.

+ References

No definition available.

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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.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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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

+ Details

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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 less than twelve months.

+ References

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

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- Definition

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.

+ Details

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Investments (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
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	$ 1,011,427		$ 2,571,006
Gross unrealized losses on investments in unrealized loss position	40,022		$ 100,332
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	8,551
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	$ 31,471
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%	0.07%
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
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Aggregate market value of investments in unrealized loss position	$ 1,011,427		$ 2,571,006
Gross unrealized losses on investments in unrealized loss position	40,022		100,332
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	8,551		62,697
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	$ 31,471		37,635
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	0.90%
Energy Sector [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation			35,978
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation			6,959
Foreign Exchange Losses [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	$ 6,030		6,090
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	22,677		$ 14,807
Limited Partnerships [Member]
Schedule of Available-for-sale Securities [Line Items]
Additional contractual commitments	$ 290,398