FINANCIAL INSTRUMENTS (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Summary of the estimated fair value of debt instruments

A summary of the estimated fair value of our debt financial instruments follows.

	March 31, 2019				December 31, 2018
	Carrying value		Estimated fair value (Level 2)		Carrying value		Estimated fair value (Level 2)
	(In thousands)
Summit Holdings 5.5% Senior Notes ($300.0 million     principal)	$	297,805	$	296,500	$	297,638	$	286,625
Summit Holdings 5.75% Senior Notes ($500.0 million     principal)		494,341		470,417		494,093		455,208