FINANCIAL INSTRUMENTS (Tables)

6 Months Ended

Jun. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation

A rollforward of our Level 3 liability measured at fair value on a recurring basis follows (in thousands).

Level 3 liability, January 1, 2018	$	362,959
Change in fair value		90,963
Level 3 liability, June 30, 2018	$	453,922

Summary of the estimated fair value of debt instruments

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

	June 30, 2018				December 31, 2017
	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)	$	297,412	$	293,875	$	297,090	$	301,750
Summit Holdings 5.75% Senior Notes ($500.0 million     principal)		493,593		474,375		493,102		501,667