Receivables and Revenue - Additional Information (Detail)	3 Months Ended	6 Months Ended
Jun. 25, 2021 USD ($) Customer	Jun. 26, 2020 Customer	Jun. 25, 2021 USD ($) Customer	Jun. 26, 2020 Customer	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Receivables And Revenue [Line Items]
Collateral held for receivables from clients	$ 4,400,000,000		$ 4,400,000,000		$ 4,035,000,000
Collateral held for securities purchased under agreements to resell	$ 1,101,000,000		$ 1,101,000,000		1,743,000,000
Fair value of collateral as percentage of amortized cost	100.00%		100.00%
Expected credit loss on collateral held for receivables from clients	$ 0		$ 0		0
Expected credit loss on partnership loans	0		0		0
Receivable from clients balance	647,000,000		647,000,000		563,000,000	$ 470,000,000
Fees from mutual fund, insurance companies and other	325,000,000		325,000,000		285,000,000	$ 291,000,000
Expected credit loss for receivables from contracts with customers	$ 0		$ 0		$ 0
Concentration risk, number of customers \| Customer	1	1	1	1
Sales Revenue Net [Member] \| Customer [Member]
Receivables And Revenue [Line Items]
Concentration Risk, Percentage	11.00%	13.00%	12.00%	14.00%

Concentration risk, number of customers.

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- Definition

Expected credit loss for receivables from contracts with customers.

+ References

No definition available.

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- Definition

Expected credit loss on collateral held for receivables from clients.

+ References

No definition available.

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- Definition

Fees from mutual fund, insurance companies and other.

+ References

No definition available.

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- Definition

Minimum fair value of collateral as percentage of amortized cost.

+ References

No definition available.

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- Definition

Partnership loans expected credit loss.

+ References

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- Definition

Receivables and revenue.

+ References

No definition available.

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- Definition

Revenue from contract with customer receivables.

+ References

No definition available.

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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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- Definition

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it is permitted by contract or custom to sell or re-pledge to counterparties as collateral.

+ References

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- Definition

Fair value of securities received as collateral against securities purchased under agreement to resell.

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