TREASURY UNITS (Details)				3 Months Ended		115 Months Ended
	Mar. 31, 2017 $ / item shares	Mar. 10, 2015 shares	Aug. 20, 2007 $ / item shares	Mar. 31, 2017 USD ($) $ / item shares	Mar. 31, 2016 USD ($) shares	Mar. 31, 2017 USD ($) $ / item shares	Mar. 06, 2008 shares
Treasury units	55,839			55,839		55,839
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	1,365,306		1,365,306
Repurchase price of depository receipts (in dollars per receipt) | $ / item						27.14
Units repurchased (in shares)				23	451
Total cost of repurchase | $				$ 42,548	$ 694,380	$ 40,274,000
General Partnership
Treasury units	559			559		559
Fixed distribution percentage of unit holders				1.00%
Number of depository receipts repurchased	162		162
Total cost of repurchase | $				$ 426	$ 6,783
Value of units required to be repurchased | $				$ 425
Repurchases required (in units)				0.2
Treasury Units
Units repurchased (in shares)				23	451
Class A
Treasury units	44,671			44,671		44,671
Fixed distribution percentage of unit holders				80.00%
Repurchase price of depository receipts (in dollars per receipt) | $ / item				62.00
Repurchase price of units (in dollars per unit) | $ / item	814.20		814.20	1,860.00
Total cost of repurchase | $				$ 34,038	$ 558,723
Class B
Treasury units	10,609			10,609		10,609
Fixed distribution percentage of unit holders				19.00%
Number of depository receipts repurchased	3,072		3,072
Total cost of repurchase | $				$ 8,084	$ 128,874
Value of units required to be repurchased | $				$ 8,084
Repurchases required (in units)				4.3
Class A
Repurchase of depository receipts | $				$ 549
Class B | General Partnership
Repurchase price of units (in dollars per unit) | $ / item	926.26		926.26