v3.8.0.1

Investments - Net Realized and Unrealized Gains (Losses) on Investment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Gain (Loss) on Investments [Line Items]
Gross gains	$ 6,856	$ 1,900	$ 9,569	$ 5,402
Gross losses	(997)	0	(1,253)	(891)
Realized gains, Net	5,859	1,900	8,316	4,511
Proceeds from sales of fixed maturities classified as available-for-sale	97,357	15,260	199,751	101,923
Net unrealized gains (losses)	49,289		49,289		$ (20,632)
Deferred income tax	(79)		(79)		(84)
Net unrealized gains (losses), net of deferred income tax	49,210		49,210		(20,716)
Change, net of deferred income tax			69,926
Available-for-sale securities [Member] | Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Gross gains	1,366	1,813	3,854	4,953
Gross losses	(997)	0	(1,253)	(891)
Realized gains, Net	369	1,813	2,601	4,062
Net unrealized gains (losses)	47,888		47,888		(23,635)
Other investments [Member]
Gain (Loss) on Investments [Line Items]
Gross gains	5,490	87	5,715	449
Gross losses	0	0	0	0
Realized gains, Net	5,490	$ 87	5,715	$ 449
Net unrealized gains (losses)	$ 1,401		$ 1,401		$ 3,003

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Investments, Change in Gross Unrealized Gain (Loss), Net of Deferred Income Tax Expense

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Amount of deferred tax liability attributable to taxable temporary differences from capitalized costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32632-109319

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The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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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 total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity and any gains or losses realized during the period from the sale of investments accounted for under the cost method of accounting and/or investments that are separately or otherwise not categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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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.

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