Trade and other receivables - Orbital receivables (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) customer	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Trade and other receivables
Orbital receivables, net	$ 361	$ 382
Impairment to long-term orbital receivables	14	14	$ 22
Changes in allowance for expected credit losses related to non-current orbital receivables
Allowance at the beginning of the period	(35)	(21)
Additions	(14)	(14)
Allowance at the end of the period	$ (49)	$ (35)	$ (21)
Accounts Receivable \| Credit Concentration Risk
Trade and other receivables
Number of customers \| customer	14
Accounts Receivable \| Credit Concentration Risk \| Largest Customer
Trade and other receivables
Concentration risk, percentage	19.00%	27.00%

The amount of impairment of long-term orbital receivables recognized during the period.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the number of customers.

+ References

No definition available.

+ Details

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- Definition

The amount of non current portion of orbital receivables.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

+ Details

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- Details

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- Details

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- Details

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