Derivative Instruments (Impact of Derivative Instruments on the Consolidated Statements of Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Gain (loss) on derivative instruments recognized in income	$ (11,049)	$ 4,399	$ 4,016
Derivative and financial instruments designated as hedges gain (loss)	(134,369)	(131,120)	211,390
Designated as Hedging Instrument
Derivative [Line Items]
Gain (loss) on derivative instruments recognized in income	22,698	26,419	12,271
Not Designated as Hedging Instrument
Derivative [Line Items]
Gain (loss) on derivative instruments recognized in income	$ (5,982)	$ (2,310)	$ 5,233