Subsequent event (Details) - USD ($)	1 Months Ended
Aug. 26, 2019	Jul. 31, 2019
Subsequent Event [Member] \| Freddie Mac [Member]
Subsequent Event [Line Items]
New Loan amount	$ 28,815,000
Berdan Court, LLC [Member]
Subsequent Event [Line Items]
Amount of deposits		$ 576,300
Berdan Court, LLC [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Percentage of acquisition	100.00%
Old loan amount	$ 17,000,000
Term of the loan	10 years
Fixed interest rate	3.54%
Proceeds from refinancing	$ 11,600,000
Berdan Court, LLC [Member] \| Subsequent Event [Member] \| Minimum [Member]
Subsequent Event [Line Items]
New loan annual interest rate	3.54%
Berdan Court, LLC [Member] \| Subsequent Event [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Old loan annual interest rate	6.09%

Face (par) amount of old debt instrument at time of issuance.

No definition available.

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- Definition

Incremental percentage increase (decrease) in the stated rate on a old debt instrument.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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