Share-Based Compensation Plans (Schedule Of Stock Option Activity) (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Share Based Compensation [Abstract]
Options Outstanding, Beginning Balance | shares	18,613,822
Options Granted | shares	11,579,119
Options Exercised | shares	(466,940)
Options Forfeited | shares	(1,186,465)
Options Expired | shares	(1,375,389)
Options Outstanding, Ending Balance | shares	27,164,147
Options Vested or expected to vest | shares	27,164,147
Options Exercisable | shares	11,785,971
Options Outstanding, Weighted Average Exercise Price, Beginning Balance | $ / shares	$ 4.15
Options Granted, Weighted Average Exercise Price | $ / shares	3.00
Options Exercised, Weighted Average Exercise Price | $ / shares	3.15
Options Forfeited, Weighted Average Exercise Price | $ / shares	3.20
Options Expired, Weighted Average Exercise Price | $ / shares	5.08
Options Outstanding, Weighted Average Exercise Price, Ending Balance | $ / shares	3.67
Options Vested or expected to vest, Weighted Average Exercise Price | $ / shares	3.67
Options Exercisable, Weighted Average Exercise Price | $ / shares	$ 4.33
Options Outstanding, Weighted Average Remaining Contractual Term	7 years 7 months 24 days
Options Vested or expected to vest, Weighted Average Remaining Contractual Term	7 years 7 months 24 days
Options Exercisable, Weighted Average Remaining Contractual Term	5 years 9 months 29 days
Options Outstanding, Aggregate Intrinsic Value | $	$ 19,782,605
Options Vested or expected to vest, Aggregate Intrinsic Value | $	19,782,605
Options Exercisable, Aggregate Intrinsic Value | $	$ 3,677,098