Investment in Available-for-Sale Securities (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	$ 1,991,977	$ 1,925,012
Available-for-sale Securities, Unrealized Gains	17,473	23,733
Available-for-sale Securities, Unrealized Losses	(14,446)	(15,944)
Available-for-sale Securities, Fair Value	1,995,004	1,932,801
U.S. federal agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	4,808	49,739
Available-for-sale Securities, Unrealized Gains	92	68
Available-for-sale Securities, Unrealized Losses	0	(117)
Available-for-sale Securities, Fair Value	4,900	49,690
Municipal securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	519,333	441,372
Available-for-sale Securities, Unrealized Gains	1,429	463
Available-for-sale Securities, Unrealized Losses	(627)	(966)
Available-for-sale Securities, Fair Value	520,135	440,869
Certificates of deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	1,450,538	1,395,990
Available-for-sale Securities, Unrealized Gains	15,571	22,904
Available-for-sale Securities, Unrealized Losses	(13,819)	(14,861)
Available-for-sale Securities, Fair Value	1,452,290	1,404,033
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	17,298	37,911
Available-for-sale Securities, Unrealized Gains	381	298
Available-for-sale Securities, Unrealized Losses	0	0
Available-for-sale Securities, Fair Value	$ 17,679	$ 38,209

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

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