Investment in Securities, Investments Classified as Available for Sale in Unrealized Loss Position (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($) Investment	Sep. 30, 2016 USD ($) Investment	Sep. 30, 2017 USD ($) Investment	Sep. 30, 2016 USD ($) Investment	Dec. 31, 2016 Investment
Schedule of Available-for-sale Securities [Line Items]
Number of investment holding in loss positions \| Investment	0	0	0	0	0
Losses on available for sale securities deemed to be other than temporary \| $	$ 0	$ 0	$ 0	$ 0

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562

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- Definition

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.

+ References

No definition available.

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