Debt (Tables)

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Schedule of long-term debt

	December 31, 2019						December 31, 2018
	Principal Value		Carrying Value (a)		Fair Value (b)		Principal Value		Carrying Value (a)		Fair Value (b)
	(Thousands)
Term Loan Facility due May 31, 2021	$	1,000,000	$	999,353	$	999,353	$	—	$	—	$	—
Senior notes:
8.125% notes due June 1, 2019	—		—		—		700,000		699,729		712,663
Floating rate notes due October 1, 2020	500,000		499,238		500,290		500,000		498,222		490,730
2.50% notes due October 1, 2020	500,000		499,228		500,950		500,000		498,198		489,690
8.81% to 9.00% series A due 2020 – 2021	35,200		35,200		37,380		35,200		35,200		37,920
4.875% notes due November 15, 2021	750,000		747,571		774,173		750,000		746,245		762,555
3.00% notes due October 1, 2022	750,000		745,579		737,025		750,000		743,972		712,980
7.42% series B due 2023	10,000		10,000		10,788		10,000		10,000		10,666
7.75% debentures due July 15, 2026	115,000		111,727		129,466		115,000		111,229		128,808
3.90% notes due October 1, 2027	1,250,000		1,241,024		1,167,763		1,250,000		1,239,866		1,085,663
Note payable to EQM	110,059		110,059		128,241		114,720		114,720		121,752
Total debt	5,020,259		4,998,979		4,985,429		4,724,920		4,697,381		4,553,427
Less: Current portion of debt (c)	16,204		16,204		17,436		704,661		704,390		717,609
Long-term debt	$	5,004,055	$	4,982,775	$	4,967,993	$	4,020,259	$	3,992,991	$	3,835,818

(a) For the note payable to EQM, the principal value represents the carrying value. For all other debt, the principal value less the unamortized debt issuance costs and debt discounts represents the carrying value.

(b) The carrying value of borrowings under the Company's Term Loan Facility approximates fair value as the interest rates are based on prevailing market rates; therefore, it is a Level 1 fair value measurement. For the note payable to EQM, fair value is measured using Level 3 inputs. For all other debt, fair value is measured using Level 2 inputs.

(c)

The Floating Rate notes and 2.50% notes due in 2020 were classified as long-term due to the repayment in February 2020 described below.