Investments - Schedule of Unrealized Net Gains (Losses) Recognized in NI on Equity Securities Still Held at Period-End (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018
Realized Investment Gains Losses [Abstract]
Net gains (losses) recognized on equity securities	$ 539	$ (1,406)
Less: Net gains (losses) recognized on equity securities sold	(49)	(49)
Net gains (losses) recognized in net income on equity securities still held as of period-end	$ 588	$ (1,357)

Net gains (losses) recognized in net income during period on equity securities.

No definition available.

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- Definition

Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714

+ Details

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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

+ Details

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- References

No definition available.

+ Details

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