TREASURY UNITS (Details)		2 Months Ended	12 Months Ended			149 Months Ended
	Mar. 10, 2015 shares	Mar. 08, 2020 USD ($) $ / item shares	Dec. 31, 2019 USD ($) $ / item shares	Dec. 31, 2018 USD ($) $ / item shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2019 USD ($) $ / item shares	Aug. 20, 2007 shares
Treasury units			58,247			58,247
Period for repurchase of depository receipts	5 years
Depository receipts authorized to be repurchased	2,000,000						300,000
Number of depository receipts repurchased				57,803		1,423,109
Repurchase price of depository receipts (in dollars per receipt) | $ / item						28.31
Units required to be repurchased (in shares)			2,408		23
Total cost of repurchase | $			$ 4,050,137		$ 42,548	$ 44,324,000
Subsequent event
Number of depository receipts repurchased		3,469
Repurchase price of depository receipts (in dollars per receipt) | $ / item		62.01
Total cost of repurchase | $		$ 215,113
General Partnership
Treasury units			583			583
Fixed distribution percentage of unit holders			1.00%
Number of depository receipts repurchased						186
Total cost of repurchase | $			$ 40,498	$ 40,498	$ 426
General Partnership | Subsequent event
Value of units required to be repurchased | $		2,689
Treasury Units
Units required to be repurchased (in shares)			2,408		23
Class A
Fixed distribution percentage of unit holders			80.00%
Repurchase price of depository receipts (in dollars per receipt) | $ / item						849.30
Total cost of repurchase | $			$ 3,240,181		$ 34,038
Class B
Fixed distribution percentage of unit holders			19.00%
Number of depository receipts repurchased						3,530
Repurchase price of depository receipts (in dollars per receipt) | $ / item						1,024.08
Total cost of repurchase | $			$ 769,458		$ 8,084
Class B | Subsequent event
Value of units required to be repurchased | $		$ 51,087
Class A
Treasury units			46,597			46,597
Repurchase price of depository receipts (in dollars per receipt) | $ / item				56.05
Repurchase price of units (in dollars per unit) | $ / item			1,681.50	1,681.50
Class A | Limited Partner
Total cost of repurchase | $				$ 3,240,181
Class B
Treasury units			11,067			11,067
Fixed distribution percentage of unit holders			19.00%
Class B | Limited Partner
Total cost of repurchase | $				$ 769,458
Treasury Units | General Partnership
Units required to be repurchased (in shares)				24.1
Treasury Units | Class B | Limited Partner
Units required to be repurchased (in shares)				457.6