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Income Taxes (Income Tax Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Statutory rate	21.00%	21.00%	34.00%
State and local taxes	(3.70%)	1.50%	1.50%
Uncertain tax position	0.00%	(139.10%)	0.00%
Goodwill impairment	(13.70%)	0.00%	0.00%
Research and development credit	1.40%	92.20%	0.00%
Stock based compensation	(0.80%)	10.00%	(14.30%)
Nondeductible compensation	(0.30%)	(7.80%)
Domestic production credit	0.00%	0.00%	(15.20%)
Other	0.90%	3.90%	(1.50%)
Effective rate	4.80%	(18.30%)	4.50%
Deferred re-measurement for rate change	0	0	(12.180)
Effective rate	4.80%	(18.30%)	(1213.50%)

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