Stockholders' Equity (Capital Stock Activity) (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares, shares outstanding, beginning (in shares)	118.9
Ordinary shares, shares outstanding, ending (in shares)	465.1	118.9
Ordinary Shares Issued
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares, shares outstanding, beginning (in shares)	119.2	119.0	113.9
Stock awards	0.6	0.2	0.6
Treasury stock purchases	0.0	0.0	0.0
Capital increase reserved for employees			1.9
Shares acquired pursuant to liquidity contract		0.0	0.0
Shares sold pursuant to liquidity contract		0.0	0.0
Dividend payment in shares		3.2	2.6
Cancellation of treasury shares		(3.2)
Net capital increases due to the merger of FMC Technologies and Technip	347.4
Treasury stock cancellation due to the merger of FMC Technologies and Technip	0.0
Treasury stock cancellations	(2.1)
Net stock purchased for employee benefit trust	0.0
Ordinary shares, shares outstanding, ending (in shares)	465.1	119.2	119.0
Ordinary Shares Held in Employee Benefit Trust
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares, shares outstanding, beginning (in shares)	0.0	0.0	0.0
Stock awards	0.0	0.0	0.0
Treasury stock purchases	0.0	0.0	0.0
Capital increase reserved for employees			0.0
Shares acquired pursuant to liquidity contract		0.0	0.0
Shares sold pursuant to liquidity contract		0.0	0.0
Dividend payment in shares		0.0	0.0
Cancellation of treasury shares		0.0
Net capital increases due to the merger of FMC Technologies and Technip	0.0
Treasury stock cancellation due to the merger of FMC Technologies and Technip	0.0
Treasury stock cancellations	0.0
Net stock purchased for employee benefit trust	0.1
Ordinary shares, shares outstanding, ending (in shares)	0.1	0.0	0.0
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ordinary shares, shares outstanding, beginning (in shares)	0.3	0.8	1.4
Stock awards	0.0	(0.4)	(0.5)
Treasury stock purchases	2.1	3.2	0.0
Capital increase reserved for employees			0.0
Shares acquired pursuant to liquidity contract		1.3	1.3
Shares sold pursuant to liquidity contract		(1.4)	(1.4)
Dividend payment in shares		0.0	0.0
Cancellation of treasury shares		(3.2)
Net capital increases due to the merger of FMC Technologies and Technip	0.0
Treasury stock cancellation due to the merger of FMC Technologies and Technip	(0.3)
Treasury stock cancellations	(2.1)
Net stock purchased for employee benefit trust	0.0
Ordinary shares, shares outstanding, ending (in shares)	0.0	0.3	0.8