Impact of Recent Accounting Pronouncements Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Equity securities, at fair value	$ 655	$ 658
Accounting Standards Update 2016-01 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Equity securities, at fair value		$ 658
Reclassification of unrealized gains on equity securities due to the adoption of ASU No. 2016-01	$ 184

Amount of the cumulative effect on retained earnings net of related income tax effect.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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For an unclassified balance sheet, this item represents investments in common and preferred stocks and other forms of securities that provide ownership interests in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(b))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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+ References

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