Supplemental cash flow information - Acquisition of DigitalGlobe (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Oct. 05, 2017
Supplemental cash flow information
Total	$ 2,273.0
DigitalGlobe
Supplemental cash flow information
Acquisition	(1,131.0)	$ (1,131.0)
Repayment of long-term debt	(1,266.0)
Settlement of transaction costs	(46.6)
Cash acquired	(170.6)	$ (170.6)
Total	$ 2,273.0

The amount recognised as of the acquisition date for cash and cash equivalents acquired in a business combination. [Refer: Cash and cash equivalents; Business combinations [member]]

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The fair value, at acquisition date, of cash transferred as consideration in a business combination. [Refer: Business combinations [member]]

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The cash outflow for payments for transaction costs in a business acquisition.

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