No definition available.

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This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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- Definition

Amount of loss realized on the sale of debt or equity securities classified as available-for-sale. Excludes other than temporary impairments (OTTI).

+ References

No definition available.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (c)-(e)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c),9(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27405-111563

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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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, Gain (Loss) on Investments (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Gain (Loss) on Investments [Line Items]
Recognized other than temporary impairments									$ 0	$ 0	$ 0
Realized gains (losses)	$ 460,000	$ (47,000)	$ (42,000)	$ (122,000)	$ (52,000)	$ 5,092,000	$ 836,000	$ 3,056,000	249,000	8,932,000	28,361,000
Change in unrealized gains (losses)									69,052,000	(5,425,000)	(33,718,000)
Gross realized gains, gross realized losses and impairment losses [Abstract]
Gross realized gains									1,599,000	11,909,000	30,039,000
Gross realized losses									(1,350,000)	(2,977,000)	(1,678,000)
Net realized investment gains	$ 460,000	$ (47,000)	$ (42,000)	$ (122,000)	$ (52,000)	$ 5,092,000	$ 836,000	$ 3,056,000	249,000	8,932,000	28,361,000
Available-for-Sale Securities
Gain (Loss) on Investments [Line Items]
Realized gains (losses)									249,000	8,932,000	28,361,000
Gross realized gains, gross realized losses and impairment losses [Abstract]
Net realized investment gains									249,000	8,932,000	28,361,000
Available-for-Sale Securities \| Fixed income
Gain (Loss) on Investments [Line Items]
Realized gains (losses)									228,000	5,310,000	28,335,000
Change in unrealized gains (losses)									69,026,000	(5,403,000)	(33,687,000)
Gross realized gains, gross realized losses and impairment losses [Abstract]
Net realized investment gains									228,000	5,310,000	28,335,000
Available-for-Sale Securities \| Equity Securities
Gain (Loss) on Investments [Line Items]
Realized gains (losses)									21,000	3,622,000	26,000
Change in unrealized gains (losses)									39,000	(36,000)	(32,000)
Gross realized gains, gross realized losses and impairment losses [Abstract]
Net realized investment gains									21,000	3,622,000	26,000
Available-for-Sale Securities \| Other
Gain (Loss) on Investments [Line Items]
Realized gains (losses)									0	0	0
Change in unrealized gains (losses)									(13,000)	14,000	1,000
Gross realized gains, gross realized losses and impairment losses [Abstract]
Net realized investment gains									$ 0	$ 0	$ 0