KEMMERER DROP (Details) $ / shares in Units, $ in Millions	Aug. 01, 2015 USD ($) $ / shares	Sep. 30, 2015
Westmoreland Kemmerer, LLC
Noncontrolling Interest [Line Items]
Contribution of outstanding equity interests	100.00%
Aggregate consideration	$ 230.0
Cash received	115.0
WMLP Series A Convertible Partnership Units received	$ 115.0
Conversion ratio of Series A Units to limited partner interests of WMLP	1
Cash distribution to holders of Common Units, minimum \| $ / shares	$ 0.22
Net assets transferred	$ 99.6
Westmoreland Resource Partners LP
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		93.80%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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