Taxes on Income (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2017
Income Taxes [Abstract]
Effective income tax rate			21.00%		35.00%
Tax refund amount	$ (30,606,000)		$ (30,606,000)
Income tax receivable	125,883,000		125,883,000
Earnings (loss) before taxes on income [Abstract]
Earnings (loss) before taxes on income	23,834,000	$ 62,709,000	(495,938,000)	$ 121,046,000
Federal [Abstract]
Current	(18,608,000)	0	(156,304,000)	0
Deferred	16,149,000	13,517,000	(7,294,000)	26,007,000
State and local [Abstract]
Current	536,000	1,686,000	618,000	3,145,000
Deferred	505,000	0	(11,294,000)	0
Foreign - current	(11,000)	66,000	36,000	(3,000)
Total Provision for taxes on income	$ (1,429,000)	15,269,000	(174,238,000)	29,149,000
COVID-19 [Member]
Income Taxes [Abstract]
Operating losses tax year	2013 2014 2015 2016 2017
Tax benefit related to CARES Act	$ (50,824,000)
Decrease in deferred tax asset	$ (77,262,000)
COVID-19 [Member] | Maximum [Member]
Income Taxes [Abstract]
Number of years net operating losses carried	5 years
United States [Member]
Earnings (loss) before taxes on income [Abstract]
Earnings (loss) before taxes on income	$ 23,861,000	62,903,000	(495,628,000)	121,655,000
Foreign [Member]
Earnings (loss) before taxes on income [Abstract]
Earnings (loss) before taxes on income	$ (27,000)	$ (194,000)	$ (310,000)	$ (609,000)