SUBSEQUENT EVENTS (Details) - Subsequent event $ / shares in Units, $ in Millions	Apr. 28, 2017 USD ($) $ / shares
Subsequent Event
Distributions declared (in dollars per unit) | $ / shares	$ 0.55
Approximate distribution to be paid (in dollars) | $	$ 32.9
ARLP
Subsequent Event
Distributions declared (in dollars per unit) | $ / shares	$ 0.4375
Approximate distribution to be paid, including incentive distributions | $	$ 52.5