Taxes on Income (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2017	Dec. 31, 2020
Income Taxes [Abstract]
Effective income tax rate	21.00%		35.00%
Income tax receivable	$ 70,528,000			$ 188,177,000
Tax refund amount	119,493,000
Loss before taxes on income [Abstract]
Loss before taxes on income	(4,011,000)	$ (519,772,000)
U.S. Federal [Abstract]
Current	0	(137,696,000)
Deferred	(603,000)	(23,443,000)
U.S. State and local [Abstract]
Current	(358,000)	82,000
Deferred	70,000	(11,799,000)
Foreign - current	0	47,000
Total provision (benefit) for taxes on income	$ (891,000)	(172,809,000)
COVID-19 [Member]
Income Taxes [Abstract]
Operating losses tax year	2013 2014 2015 2016 2017
Tax benefit related to CARES Act		(50,824,000)
COVID-19 [Member] | Maximum [Member]
Income Taxes [Abstract]
Number of years net operating losses carried	5 years
United States [Member]
Loss before taxes on income [Abstract]
Loss before taxes on income	$ (3,619,000)	(519,489,000)
Foreign [Member]
Loss before taxes on income [Abstract]
Loss before taxes on income	$ (392,000)	$ (283,000)