Financing Arrangements and Long-Term Debt - Schedule of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Nov. 30, 2019	Oct. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total notes payable	$ 2,828,668			$ 2,800,000
Unamortized debt issuance cost and discount on notes payable	(25,287)			(23,627)
Total notes payable, net of unamortized discount	2,803,381			2,776,373
Capitalized lease obligation, due through March 2029 ¹	0			8,613
Total debt including current maturities	2,803,381			2,784,986
Senior Unsecured Revolving Credit Facility	0			325,000
Current maturities ²	0			(668)	[1]
Total long-term debt	2,803,381			3,109,318	[1]
4.00% notes, due June 2022
Debt Instrument [Line Items]
Total notes payable	260,251			$ 500,000
Interest Rate		4.00%		4.00%
4.45% notes, due December 2022 ¹
Debt Instrument [Line Items]
Total notes payable	318,417			$ 600,000
Interest Rate		4.45%	3.70%	4.45%
6.875% notes, due August 2024
Debt Instrument [Line Items]
Total notes payable	550,000			$ 550,000
Interest Rate				6.875%
5.75% notes, due August 2025
Debt Instrument [Line Items]
Total notes payable	550,000			$ 550,000
Interest Rate				5.75%
5.875% notes, due December 2027
Debt Instrument [Line Items]
Total notes payable	550,000			$ 0
Interest Rate		5.875%		5.875%
7.05% notes, due May 2029
Debt Instrument [Line Items]
Total notes payable	250,000			$ 250,000
Interest Rate				7.05%
5.875% notes, due December 2042 ¹
Debt Instrument [Line Items]
Total notes payable	$ 350,000			$ 350,000
Interest Rate				5.875%

[1] Reclassified to conform with current presentation (see Note E)