Shareholders' Equity - Schedule of weighted average shares outstanding (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity [Abstract]
Basic weighted-average ordinary shares outstanding	245,200,000	258,500,000	268,100,000
Dilutive effect of potentially issuable shares	1,800,000	2,200,000	2,200,000
Diluted weighted-average ordinary shares outstanding	247,000,000	260,700,000	270,300,000
Antidilutive securities excluded from computation of earnings per share (in shares)	0	0	0