Loans - Secured Loans in Non-Accrual Status (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2018 USD ($) MortgageLoan	Dec. 31, 2017 USD ($) MortgageLoan
Loans Details Secured Loans In Nonaccrual Status [Line Items]
Number of secured loans \| MortgageLoan	93	93
Loans - principal (in Dollars)	$ 57,865,391	$ 54,768,689
Accrued interest	$ 426,538	$ 409,867
Non-Accrual Status [Member]
Loans Details Secured Loans In Nonaccrual Status [Line Items]
Number of secured loans \| MortgageLoan	1	1
Loans - principal (in Dollars)	$ 152,405	$ 151,637
Accrued interest	8,874	11,025
Foregone interest	7,535	4,306
Principal [Member] \| Non-Accrual Status [Member]
Loans Details Secured Loans In Nonaccrual Status [Line Items]
Loans - principal (in Dollars)	139,162	139,643
Advances [Member] \| Non-Accrual Status [Member]
Loans Details Secured Loans In Nonaccrual Status [Line Items]
Loans - principal (in Dollars)	$ 4,369	$ 969

Loans details secured loans in nonaccrual status.

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- Definition

Loans receivable foregone interest.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ 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 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ 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(c))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Indicates the number of mortgages under each classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29.3)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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