Subsequent events (Details) - Subsequent Event - Discontinued operations - Management Services $ in Millions	Oct. 12, 2019 USD ($)
Subsequent Events
Consideration received	$ 2,405
Contingent consideration, prior work claims	$ 150

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration