Basic and Diluted Net Loss Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Basic and Diluted Loss Per Share	Basic and Diluted Net Loss Per ShareBasic and diluted net loss attributable to SGC per share were the same, as any additional common stock equivalents would be anti-dilutive. We excluded 2 million, 1 million and 2 million stock options from the calculation of diluted weighted-average net loss attributable to SGC per share for the years ended December 31, 2020, 2019 and 2018, respectively, which would be anti-dilutive due to the net loss attributable to SGC in those periods. In addition, we excluded 3 million RSUs from the calculation of diluted weighted-average net loss attributable to SGC per share for each of the years ended December 31, 2020, 2019 and 2018, which would be anti-dilutive due to the net loss attributable to SGC in those periods.