Line items represent reporting 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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The aggregate net change in the difference between the fair value and the carrying value, or in the comparative fair values, of marketable securities and/or any unrealized gains or losses on investments that are separately or otherwise not categorized as trading, available-for-sale or held-to-maturity.

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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INVESTMENTS - Realized and Unrealized Gains (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
INVESTMENTS
Net realized gains (losses), excluding OTTI									$ 34,740	$ 39,829	$ 32,182
OTTI									(95)	0	0
Realized Gain (Loss) on Marketable Securities, Cost Method Investments and Other Investments, Total	$ 11,283	$ 9,252	$ 2,710	$ 11,400	$ 14,207	$ 7,534	$ 4,802	$ 13,286	34,645	39,829	32,182
Net changes in unrealized gains (losses) on investments:									(1,791)	(72,935)	54,393
Net realized gains (losses) and changes in unrealized gains (losses) on investments									32,854	(33,106)	86,575
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal										6,698
Goodwill, Impairment Loss									7,200
Debt securities \| Available for sale securities
INVESTMENTS
Net realized gains (losses), excluding OTTI									4,314	10,832	3,955
Net changes in unrealized gains (losses) on investments:									(10,972)	(26,929)	37,880
Debt securities \| Held-to-maturity Securities
INVESTMENTS
Net realized gains (losses), excluding OTTI											4
Equity securities
INVESTMENTS
Net realized gains (losses), excluding OTTI									38,709	22,107	29,468
Net changes in unrealized gains (losses) on investments:									8,659	(44,120)	17,300
Other
INVESTMENTS
Net realized gains (losses), excluding OTTI									(8,283)	192	(1,245)
Equity Method Investments [Member]
INVESTMENTS
Net changes in unrealized gains (losses) on investments:									$ 522	$ (1,886)	$ (787)