Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Supplemental Cash Flow Information [Abstract]
Interest (1)	[1]	$ 47,771	$ 50,103
Income Taxes, Net of Refunds Received		(9,307)	3,554
Interest Costs Capitalized		7,000	5,000
Accrued Capital Expenditures		706,000	593,000
Non-Cash Property Exchanges		$ 62,000	9,000
Non-Cash Investing From Other Property, Plant and Equipment			$ 48,000

[1] Net of capitalized interest of $7 million and $5 million for the three months ended March 31, 2019 and 2018, respectively.