Fair Value Disclosures (Assets and Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands		Mar. 31, 2020	Dec. 31, 2019
Long-term Debt		$ 3,854,062	$ 3,102,830
Derivative Asset, Fair Value, Gross Asset		14,900	1,100
Derivative Liability, Fair Value, Gross Liability		(14,400)	(4,500)
Fair Value, Recurring [Member] | Cross Currency Swaps [Member]
Derivative Asset, Fair Value, Gross Asset	[1]	14,936	828
Fair Value, Recurring [Member] | Cross Currency Swaps [Member] | Fair Value, Inputs, Level 2 [Member]
Derivative Asset, Fair Value, Gross Asset	[1]	14,936	828
Fair Value, Recurring [Member] | Interest Rate Swap [Member]
Derivative Asset, Fair Value, Gross Asset	[1]		(225)
Derivative Liability, Fair Value, Gross Liability	[2]	(14,447)	(4,495)
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Derivative Asset, Fair Value, Gross Asset	[1]		(225)
Derivative Liability, Fair Value, Gross Liability	[2]	(14,447)	$ (4,495)
Variable Rate Converted to Fixed Rate [Member]
Long-term Debt		$ 425,000

[1] Included in "Other assets" in the accompanying consolidated balance sheets.

[2] Included in "Accounts payable and accrued liabilities" in the accompanying consolidated balance sheets.