Derivatives and Hedging Activities (Schedule of Effects of Interest Rate Swaps on the Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Qualifying Hedges [Member] | Other Long-Term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate swap agreements in a fair value liability position	$ 162,260	$ 42,698
Non-Qualifying Hedging [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate swap agreements in a fair value asset position	116,451	47,583
Non-Qualifying Hedging [Member] | Other Long-Term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate swap agreements in a fair value liability position	$ 113,259	$ 47,583