Summary of Significant Accounting Policies - Schedule of Lease Receivables Relating to Sales-Type Leases (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Sales-type Lease, Net Investment in Lease, Past Due [Line Items]
Gross lease receivables	$ 178	$ 102
Unearned interest income	(18)	(11)
Net investment in sales-type leases	160	91
Prepaid Expenses and Other Current Assets [Member]
Sales-type Lease, Net Investment in Lease, Past Due [Line Items]
Net investment in sales-type leases	30	17
Other Assets [Member]
Sales-type Lease, Net Investment in Lease, Past Due [Line Items]
Net investment in sales-type leases	$ 130	$ 74

Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919379-209981

Name:	us-gaap_SalesTypeLeaseLeaseReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant