TREASURY UNITS (Details)				1 Months Ended		3 Months Ended		6 Months Ended	9 Months Ended	132 Months Ended	142 Months Ended
	Mar. 10, 2015 shares	Aug. 31, 2007 $ / item shares	Aug. 20, 2007 shares	Nov. 06, 2019 USD ($) $ / item shares	Sep. 30, 2007 $ / item shares	Mar. 31, 2019 $ / item shares	Dec. 31, 2007 $ / item shares	Jun. 30, 2019 $ / item shares	Sep. 30, 2019 USD ($) $ / item shares	Dec. 31, 2018 $ / item shares	Jun. 30, 2019 USD ($) $ / item	Mar. 06, 2008 shares
Treasury units									58,044
Period for repurchase of depository receipts	5 years		12 months
Depository receipts authorized to be repurchased	2,000,000		300,000									1,500,000
Number of depository receipts repurchased		1,418,234			1,418,234		1,418,234	1,418,234		1,418,234
Repurchase price of depository receipts (in dollars per receipt) | $ / item											28.20
Units required to be repurchased (in shares)									2,205
Total cost of repurchase | $									$ 3,680,570		$ 43,954,000
Subsequent event
Number of depository receipts repurchased				1,879
Repurchase price of depository receipts (in dollars per receipt) | $ / item				59.98
Total cost of repurchase | $				$ 110,860
General Partnership
Treasury units									581
Fixed distribution percentage of unit holders									1.00%
Number of depository receipts repurchased		184			184	184				184
Total cost of repurchase | $									$ 36,803
Value of units required to be repurchased | $									$ 36,803
Repurchases required (in units)									22
General Partnership | Subsequent event
Units required to be repurchased (in shares)				1
Value of units required to be repurchased | $				$ 1,018
Treasury Units
Units required to be repurchased (in shares)									2,205
Class A
Treasury units									46,435
Fixed distribution percentage of unit holders									80.00%
Repurchase price of units (in dollars per unit) | $ / item		845.99			845.99	845.99				845.99
Total cost of repurchase | $									$ 2,944,508
Class B
Treasury units									11,028
Fixed distribution percentage of unit holders									19.00%
Number of depository receipts repurchased		3,491			3,491	3,491				3,491
Total cost of repurchase | $									$ 699,259
Class B | Subsequent event
Units required to be repurchased (in shares)				15
Value of units required to be repurchased | $				$ 26,320
Class B
Value of units required to be repurchased | $									$ 699,259
Class B | General Partnership
Repurchase price of units (in dollars per unit) | $ / item		1,015.36			1,015.36		1,015.36	1,015.36		1,015.36
Repurchases required (in units)									419
Treasury Units
Repurchase price of depository receipts (in dollars per receipt) | $ / item									55.63
Units required to be repurchased (in shares)									52,928
Repurchase price of units (in dollars per unit) | $ / item									1,668.90
Total cost of repurchase | $									$ 2,944,507