Subsequent events (Details) - Subsequent Events [Member] - Rouse Services LLC [Member] $ in Millions	Oct. 28, 2020 USD ($)
Business combinations
Voting equity interests acquired, percentage	100.00%
Total consideration	$ 275
Cash consideration	250
Common stock consideration	$ 25

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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