v3.19.3.a.u2

PARTNERS' EQUITY Table 5 - Cash Distributions Declared - General Partner and Common Limited Partners (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Distribution Made to Limited Partner [Line Items]
Cash distributions applicable to common unitholders (distribution earned)	$ 65,128	$ 64,660	$ 64,658	$ 64,690
Common Limited Partner [Member]
Distribution Made to Limited Partner [Line Items]
Cash distributions per unit applicable to limited partners	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 2.40	$ 2.40	$ 4.38
Distribution date of record (distribution earned)	Feb. 10, 2020	Nov. 08, 2019	Aug. 07, 2019	May 08, 2019
Distribution payment date	Feb. 14, 2020	Nov. 14, 2019	Aug. 13, 2019	May 14, 2019

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Amount of equity impact of cash distribution declared to unit-holder of limited partnership (LP).

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Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

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