Investments - Schedule of Net Impairment Losses Recognized in Earnings for Available-for-sale Securities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Total other-than-temporary impairment losses	$ 478	$ 1,564	$ 3,308	$ 2,433
Other-than-temporary impairment losses, investments, portion recognized in earnings, net	478	1,564	3,308	2,433
Does not intend to sell or more-likely-than-not will not be required to sell before recovery [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Total other-than-temporary impairment losses	445	150	1,374	251
Other-than-temporary impairment losses, investments, portion recognized in earnings, net	445	150	1,374	251
Intends to sell or more-likely-than-not will be required to sell before recovery [Member]
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Other-than-temporary impairment losses, investments, portion recognized in earnings, net	$ 33	$ 1,414	$ 1,934	$ 2,182

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560

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+ References

No definition available.

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- Definition

The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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