Per Share Information (Reconciliation of the Numerators and Denominators of the Basic and Diluted Per Share Computations) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Per Share Information
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 114	$ 119
Dividends on preferred stock	28	0
Net income (loss) attributable to CCIC common stockholders for basic and diluted computations	$ 86	$ 119
Basic weighted-average number of common stock outstanding	409	361
Effect of assumed dilution from potential common shares relating to restricted stock units	1	1
Diluted weighted-average number of common shares outstanding	410	362
Basic	$ 0.21	$ 0.33
Diluted	$ 0.21	$ 0.33