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Distributions and Net Income Per Limited Partner Unit (Distributions Declared) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	May 03, 2021	Mar. 31, 2021	Mar. 31, 2020
Distribution Made to Limited Partner [Line Items]
Net income in excess of distribution (distribution in excess of net income)		$ (1,447)	$ 1,156
Net income attributable to the Partnership		$ 15,146	$ 17,747
Weighted average limited partner units outstanding (basic and diluted) (in units)		35,198,903	35,194,545
Distributions declared		$ 16,593	$ 16,591
IDR Holders
Distribution Made to Limited Partner [Line Items]
Net income in excess of distribution (distribution in excess of net income)		0	0
Net income attributable to the Partnership		0	0
Distributions declared with respect to the incentive distribution rights		0	0
Common units
Distribution Made to Limited Partner [Line Items]
Net income in excess of distribution (distribution in excess of net income)		(1,447)	1,156
Net income attributable to the Partnership		$ 15,146	$ 17,747
Weighted average limited partner units outstanding (basic and diluted) (in units)		35,198,903	35,194,545
Distributions declared		$ 16,593	$ 16,591
Common units (in usd per share)		$ 0.43	$ 0.50
Cash Distribution \| Common units
Distribution Made to Limited Partner [Line Items]
Distributions declared		$ 16,593	$ 16,591
Cash Distribution \| Common And Subordinated Units [Member]
Distribution Made to Limited Partner [Line Items]
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders (in usd per share)		$ 1.2938
Cash Distribution \| Common And Subordinated Units [Member] \| Subsequent Event
Distribution Made to Limited Partner [Line Items]
Distribution declared per unit (in usd per unit)	$ 0.4714
Above $1.2938 up to $1.4063 \| Minimum
Distribution Made to Limited Partner [Line Items]
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders (in usd per share)		1.2938
Above $1.2938 up to $1.4063 \| Maximum
Distribution Made to Limited Partner [Line Items]
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders (in usd per share)		$ 1.4063
Above $1.2938 up to $1.4063 \| Unit Holders
Distribution Made to Limited Partner [Line Items]
Incentive Distribution, Marginal Percentage Interest in Distributions		85.00%
Above $1.2938 up to $1.4063 \| IDR Holders
Distribution Made to Limited Partner [Line Items]
Incentive Distribution, Marginal Percentage Interest in Distributions		15.00%
Above $1.4063 up to $1.6875 \| Minimum
Distribution Made to Limited Partner [Line Items]
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders (in usd per share)		$ 1.4063
Above $1.4063 up to $1.6875 \| Maximum
Distribution Made to Limited Partner [Line Items]
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders (in usd per share)		$ 1.6875
Above $1.4063 up to $1.6875 \| Unit Holders
Distribution Made to Limited Partner [Line Items]
Incentive Distribution, Marginal Percentage Interest in Distributions		75.00%
Above $1.4063 up to $1.6875 \| IDR Holders
Distribution Made to Limited Partner [Line Items]
Incentive Distribution, Marginal Percentage Interest in Distributions		25.00%
Above $1.6875 \| Minimum
Distribution Made to Limited Partner [Line Items]
Incentive Distribution Rights, Target Distribution Per Unit Requiring Marginal Percentage Distribution to IDR Holders (in usd per share)		$ 1.6875
Above $1.6875 \| Unit Holders
Distribution Made to Limited Partner [Line Items]
Incentive Distribution, Marginal Percentage Interest in Distributions		50.00%
Above $1.6875 \| IDR Holders
Distribution Made to Limited Partner [Line Items]
Incentive Distribution, Marginal Percentage Interest in Distributions		50.00%