Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Financial assets and liabilities measured at fair value on a recurring basis

The following fair value hierarchy table presents information about the Company's financial assets and liabilities measured at fair value on a recurring basis:

(In thousands)	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance at    December 31,   2017
Assets
Deferred compensation plan	$	14,966	$	—	$	—	$	14,966
Derivative instruments	—		—		2,239		2,239
Total assets	$	14,966	$	—	$	2,239	$	17,205
Liabilities
Deferred compensation plan	$	29,145	$	—	$	—	$	29,145
Derivative instruments	—		—		30,637		30,637
Total liabilities	$	29,145	$	—	$	30,637	$	59,782

(In thousands)	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance at    December 31,   2016
Assets
Deferred compensation plan	$	12,587	$	—	$	—	$	12,587
Derivative instruments	—		—		2,991		2,991
Total assets	$	12,587	$	—	$	2,991	$	15,578
Liabilities
Deferred compensation plan	$	24,169	$	—	$	—	$	24,169
Derivative instruments	—		21,400		18,859		40,259
Total liabilities	$	24,169	$	21,400	$	18,859	$	64,428

Fair Value of Financial Assets and Liabilities Classified as Level 3

The following table sets forth a reconciliation of changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy:

	Year Ended December 31,
(In thousands)	2017			2016			2015
Balance at beginning of period	$	(15,868	)	$	—		$	85,958
Total gain (loss) included in earnings	(1,866		)	(17,886		)	32,864
Settlement (gain) loss	(10,664		)	2,018			(118,822		)
Balance at end of period	$	(28,398	)	$	(15,868	)	$	—
Change in unrealized gains (losses) relating to assets and liabilities still held at the end of the period	$	(28,398	)	$	(15,868	)	$	—

Carrying amounts and fair values of long-term debt

The carrying amount and fair value of debt is as follows:

	December 31, 2017						December 31, 2016
(In thousands)	Carrying Amount			Estimated Fair Value			Carrying Amount		Estimated Fair Value
Long-term debt	$	1,521,891		$	1,527,624		$	1,520,530	$	1,463,643
Current maturities	(304,000		)	(312,055		)	—		—
Long-term debt, excluding current maturities	$	1,217,891		$	1,215,569		$	1,520,530	$	1,463,643