Earnings (Loss) Per Common Share - Computation of Diluted Earnings Loss Per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	68,789	34,354	67,454	30,323
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	1,650	3,709	1,650	3,709
Options and RSU
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	26,359	14,971	26,359	14,966
Series A Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	933	933	933
DBOT contingent consideration
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	1,197	2,323	1,197	2,323
Convertible promissory note and interest
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	38,650	12,418	37,315	9,325