Investment in Available-for-Sale Securities (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	$ 1,925,012	$ 2,540,490
Available-for-sale Securities, Gross Unrealized Gains	23,733	14,824
Available-for-sale Securities, Gross Unrealized Losses	(15,944)	(28,772)
Available-for-sale Securities, Fair Value	1,932,801us-gaap_AvailableForSaleSecurities	2,526,542us-gaap_AvailableForSaleSecurities
U.S. federal agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	49,739	90,549
Available-for-sale Securities, Gross Unrealized Gains	68	93
Available-for-sale Securities, Gross Unrealized Losses	(117)	(277)
Available-for-sale Securities, Fair Value	49,690	90,365
Municipal securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	441,372	735,826
Available-for-sale Securities, Gross Unrealized Gains	463	2,175
Available-for-sale Securities, Gross Unrealized Losses	(966)	(6)
Available-for-sale Securities, Fair Value	440,869	737,995
Certificates of deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	1,395,990	1,539,377
Available-for-sale Securities, Gross Unrealized Gains	22,904	12,281
Available-for-sale Securities, Gross Unrealized Losses	(14,861)	(19,398)
Available-for-sale Securities, Fair Value	1,404,033	1,532,260
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Cost	37,911	174,738
Available-for-sale Securities, Gross Unrealized Gains	298	275
Available-for-sale Securities, Gross Unrealized Losses	0	(9,091)
Available-for-sale Securities, Fair Value	$ 38,209	$ 165,922

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=28360136&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=6871852&loc=d3e26610-111562

+ Details

Name:	us-gaap_AvailableForSaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

-Subparagraph (c)

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

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MunicipalBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: