INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Balance Sheet) (Details)	Sep. 30, 2020 USD ($) property	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	May 31, 2018 USD ($)	Oct. 28, 2009 USD ($) item	Feb. 28, 2007 item	Oct. 03, 2005 USD ($) item	Mar. 07, 2005 item	Mar. 02, 2005 USD ($) item	Sep. 30, 2004 USD ($) item	Aug. 31, 2004 USD ($) item	Nov. 30, 2001 USD ($) item
ASSETS
Rental Properties	$ 267,905,211	$ 278,363,988
Cash and Cash Equivalents	16,847,883	7,546,324
Rents Receivable	1,124,853	484,610
Real Estate Tax Escrows	503,431	446,781
Prepaid Expenses and Other Assets	5,265,952	6,021,544
Total Assets	293,087,027	294,293,649
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	283,927,890	281,771,246
Accounts Payable and Accrued Expenses	3,765,731	4,274,266
Advance Rental Payments and Security Deposits	7,218,279	8,101,835
Total Liabilities	332,417,188	332,117,436
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(39,330,161)	(37,823,787)	$ (38,181,542)	$ (35,624,010)
Total Liabilities and Partners' Capital	293,087,027	294,293,649
Investment in Unconsolidated Joint Ventures	1,439,697	1,430,402
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	$ (20,505,288)	$ (19,970,089)
NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%		50.00%
NERA 40%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	40.00%		40.00%
Investment Properties
ASSETS
Rental Properties	$ 116,833,825		$ 121,606,956
Cash and Cash Equivalents	4,240,170		2,320,898
Rents Receivable	830,257		341,450
Real Estate Tax Escrows	246,827		245,680
Prepaid Expenses and Other Assets	2,085,019		2,140,643
Total Assets	124,236,098		126,655,627
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	166,332,832		166,427,083
Accounts Payable and Accrued Expenses	1,167,605		1,260,246
Advance Rental Payments and Security Deposits	3,067,704		3,685,761
Total Liabilities	170,568,141		171,373,090
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(46,332,043)		(44,717,463)
Total Liabilities and Partners' Capital	124,236,098		126,655,627
Investment in Unconsolidated Joint Ventures	1,439,697		1,439,724
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	(20,505,288)		(19,786,262)
Total Investment in Unconsolidated Joint Ventures (Net)	$ (19,065,591)		$ (18,346,539)
Total units/ condominiums
Total	865		913
Units to be retained	690		690
Units to be sold			223
Total number of units sold	175		223
Investment Properties | Residential buildings
Total units/ condominiums
Total	862		910
Investment Properties | Commercial
Total units/ condominiums
Total	3		3
Hamilton Essex 81
ASSETS
Rental Properties	$ 6,758,283		$ 6,966,539
Cash and Cash Equivalents	281,585		342,346
Rents Receivable	220,578		243,635
Real Estate Tax Escrows	66,248		72,146
Prepaid Expenses and Other Assets	319,434		309,502
Total Assets	7,646,128		7,934,168
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	9,931,055		9,917,266
Accounts Payable and Accrued Expenses	53,569		85,115
Advance Rental Payments and Security Deposits	202,659		286,274
Total Liabilities	10,187,283		10,288,655
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(2,541,155)		(2,354,487)
Total Liabilities and Partners' Capital	7,646,128		$ 7,934,168
Partners' Capital % - NERA			50.00%
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	$ (1,270,578)		$ (1,177,243)
Total units/ condominiums
Total	49		49						48
Units to be retained	49		49
Hamilton Essex 81 | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%
Hamilton Essex 81 | Residential buildings
Total units/ condominiums
Total	48		48
Hamilton Essex 81 | Commercial
Total units/ condominiums
Total	1		1
Hamilton Essex Development
ASSETS
Rental Properties	$ 2,591,281		$ 2,593,771
Cash and Cash Equivalents	70,894		44,020
Rents Receivable	48,878		28,041
Prepaid Expenses and Other Assets	84,898		102,546
Total Assets	2,795,951		2,768,378
LIABILITIES AND PARTNERS' CAPITAL
Accounts Payable and Accrued Expenses	2,400		1,964
Total Liabilities	2,400		1,964
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	2,793,551		2,766,414
Total Liabilities and Partners' Capital	2,795,951		$ 2,768,378
Partners' Capital % - NERA			50.00%
Investment in Unconsolidated Joint Ventures	$ 1,396,776		$ 1,383,207
Total units/ condominiums
Total	1		1
Units to be retained	1		1
Hamilton Essex Development | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%
Hamilton Essex Development | Commercial
Total units/ condominiums
Total	1		1
345 Franklin
ASSETS
Rental Properties	$ 5,439,844		$ 5,748,520
Cash and Cash Equivalents	183,638		156,545
Rents Receivable	11,367		5,426
Real Estate Tax Escrows	57,079		53,249
Prepaid Expenses and Other Assets	82,969		86,574
Total Assets	5,774,897		6,050,314
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	9,149,766		9,346,663
Accounts Payable and Accrued Expenses	101,651		103,905
Advance Rental Payments and Security Deposits	217,832		293,858
Total Liabilities	9,469,249		9,744,426
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(3,694,352)		(3,694,112)
Total Liabilities and Partners' Capital	5,774,897		$ 6,050,314
Partners' Capital % - NERA			50.00%										50.00%
Investment in Unconsolidated Joint Ventures													$ 1,533,000
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	$ (1,847,175)		$ (1,847,056)
Total units/ condominiums
Total	40		40										40
Units to be retained	40		40
345 Franklin | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%
345 Franklin | Residential buildings
Total units/ condominiums
Total	40		40
Hamilton 1025
ASSETS
Rental Properties	$ 85,635		$ 86,850
Cash and Cash Equivalents	12,305		24,496
Rents Receivable	811
Prepaid Expenses and Other Assets	2,129		1,761
Total Assets	100,880		113,107
LIABILITIES AND PARTNERS' CAPITAL
Accounts Payable and Accrued Expenses	15,038		7,976
Advance Rental Payments and Security Deposits			1,310
Total Liabilities	15,038		9,286
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	85,842		103,821
Total Liabilities and Partners' Capital	100,880		$ 113,107
Partners' Capital % - NERA			50.00%							50.00%
Investment in Unconsolidated Joint Ventures	$ 42,921		$ 51,910							$ 2,352,000
Total units/ condominiums
Total	176		176							176
Units to be retained	1		1							(49)
Units to be sold			175
Total number of units sold	175		175
Hamilton 1025 | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%
Hamilton 1025 | Residential buildings
Total units/ condominiums
Total	175		175
Hamilton 1025 | Commercial
Total units/ condominiums
Total	1		1
Hamilton Bay Apts
ASSETS
Cash and Cash Equivalents			$ 10,775
Prepaid Expenses and Other Assets			2,951
Total Assets			13,726
LIABILITIES AND PARTNERS' CAPITAL
Accounts Payable and Accrued Expenses			4,411
Advance Rental Payments and Security Deposits			101
Total Liabilities			4,512
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively			9,214
Total Liabilities and Partners' Capital			$ 13,726
Partners' Capital % - NERA			50.00%					50.00%
Investment in Unconsolidated Joint Ventures			$ 4,607					$ 2,500,000
Total units/ condominiums
Total			48					168
Units to be retained | item							(48)	(48)
Units to be sold			48
Total number of units sold			48
Hamilton Bay Apts | Residential buildings
Total units/ condominiums
Total			48
Hamilton Minuteman
ASSETS
Rental Properties	$ 5,077,525		$ 5,413,076
Cash and Cash Equivalents	210,705		120,874
Rents Receivable			2,202
Real Estate Tax Escrows	31,378		28,147
Prepaid Expenses and Other Assets	26,428		26,661
Total Assets	5,346,036		5,590,960
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	5,910,322		5,902,139
Accounts Payable and Accrued Expenses	64,341		57,338
Advance Rental Payments and Security Deposits	157,932		141,128
Total Liabilities	6,132,595		6,100,605
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(786,559)		(509,645)
Total Liabilities and Partners' Capital	5,346,036		$ 5,590,960
Partners' Capital % - NERA			50.00%								50.00%
Investment in Unconsolidated Joint Ventures											$ 5,075,000
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	$ (393,280)		$ (254,823)
Total units/ condominiums
Total	42		42								42
Units to be retained	42		42
Hamilton Minuteman | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%
Hamilton Minuteman | Residential buildings
Total units/ condominiums
Total	42		42
Hamilton on Main Apts
ASSETS
Rental Properties	$ 15,343,928		$ 16,075,655
Cash and Cash Equivalents	610,816		172,829
Rents Receivable	46,780		13,651
Real Estate Tax Escrows	92,122		92,138
Prepaid Expenses and Other Assets	162,421		174,851
Total Assets	16,256,067		16,529,124
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	16,837,132		16,821,081
Accounts Payable and Accrued Expenses	168,318		181,510
Advance Rental Payments and Security Deposits	435,679		443,274
Total Liabilities	17,441,129		17,445,865
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(1,185,062)		(916,741)
Total Liabilities and Partners' Capital	16,256,067		$ 16,529,124
Partners' Capital % - NERA			50.00%									50.00%
Investment in Unconsolidated Joint Ventures												$ 8,000,000
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	$ (592,531)		$ (458,371)
Total units/ condominiums
Total	148		148									280
Units to be retained	148		148
Hamilton on Main Apts | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	50.00%
Hamilton on Main Apts | Residential buildings
Total units/ condominiums
Total	148		148
Dexter Park
ASSETS
Rental Properties	$ 81,537,329		$ 84,722,545
Cash and Cash Equivalents	2,870,227		1,449,013
Rents Receivable	501,843		48,495
Prepaid Expenses and Other Assets	1,406,740		1,435,797
Total Assets	86,316,139		87,655,850
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	124,504,557		124,439,934		$ 82,000,000
Accounts Payable and Accrued Expenses	762,288		818,027
Advance Rental Payments and Security Deposits	2,053,602		2,519,816
Total Liabilities	127,320,447		127,777,777
Partners' Capital 121,756 and 121,978 units outstanding in 2020 and 2019 respectively	(41,004,308)		(40,121,927)
Total Liabilities and Partners' Capital	86,316,139		$ 87,655,850
Partners' Capital % - NERA			40.00%			40.00%
Investment in Unconsolidated Joint Ventures						$ 15,925,000
Distribution and Loss in Excess of investments in Unconsolidated Joint Venture	$ (16,401,724)		$ (16,048,771)
Total units/ condominiums
Total	409		409			409
Units to be retained	409		409
Dexter Park | NERA 50%
LIABILITIES AND PARTNERS' CAPITAL
Partners' Capital % - NERA	40.00%
Dexter Park | Residential buildings
Total units/ condominiums
Total	409		409