Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Schedule of Cash and Cash Equivalents

The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the consolidated balance sheets to the total of the amounts shown in the consolidated statements of cash flows.

As of December 31,	2018		2017
Cash and cash equivalents	$	605.0	$	733.9
Restricted cash	19.1		30.2
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$	624.1	$	764.1

Schedule of Restricted Cash and Cash Equivalents

The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the consolidated balance sheets to the total of the amounts shown in the consolidated statements of cash flows.

As of December 31,	2018		2017
Cash and cash equivalents	$	605.0	$	733.9
Restricted cash	19.1		30.2
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$	624.1	$	764.1