Fair Values of Assets and Liabilities - Fair Value of Other Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets
Held to maturity securities:	$ 156,371	$ 159,452
U.S. agency mortgage-backed securities
Assets
Held to maturity securities:	156,371	159,452
Carrying Amount
Assets
Cash and cash equivalents	18,945	28,764
Cash and investments segregated and on deposit for regulatory purposes	12,080	11,438
Receivables from brokerage clients — net	71,118	68,629
Held to maturity securities:	156,371	159,452
Bank loans – net	40,783	40,439
Other assets	5,706	4,960
Liabilities
Bank deposits	269,460	289,953
Payables to brokerage clients	84,005	84,786
Accrued expenses and other liabilities	7,750	7,609
Other short-term borrowings	8,405	6,553
Federal Home Loan Bank borrowings	24,000	26,400
Long-term debt	22,790	26,043
Carrying Amount \| Residential real estate \| First Mortgages
Assets
Bank loans – net	26,174	26,121
Carrying Amount \| Residential real estate \| HELOCs
Assets
Bank loans – net	454	477
Carrying Amount \| Pledged asset lines
Assets
Bank loans – net	13,841	13,548
Carrying Amount \| Other
Assets
Bank loans – net	314	293
Carrying Amount \| U.S. agency mortgage-backed securities
Assets
Held to maturity securities:	156,371	159,452
Portion at Other than Fair Value Measurement
Assets
Cash and cash equivalents	18,945	28,764
Cash and investments segregated and on deposit for regulatory purposes	12,080	11,438
Receivables from brokerage clients — net	71,118	68,629
Held to maturity securities:	142,340	147,091
Bank loans – net	37,837	37,575
Other assets	5,706	4,960
Liabilities
Bank deposits	269,460	289,953
Payables to brokerage clients	84,005	84,786
Accrued expenses and other liabilities	7,750	7,609
Other short-term borrowings	8,405	6,553
Federal Home Loan Bank borrowings	24,000	26,400
Long-term debt	21,727	25,000
Portion at Other than Fair Value Measurement \| Residential real estate \| First Mortgages
Assets
Bank loans – net	23,198	23,226
Portion at Other than Fair Value Measurement \| Residential real estate \| HELOCs
Assets
Bank loans – net	484	508
Portion at Other than Fair Value Measurement \| Pledged asset lines
Assets
Bank loans – net	13,841	13,548
Portion at Other than Fair Value Measurement \| Other
Assets
Bank loans – net	314	293
Portion at Other than Fair Value Measurement \| U.S. agency mortgage-backed securities
Assets
Held to maturity securities:	142,340	147,091
Portion at Other than Fair Value Measurement \| Level 1
Assets
Cash and cash equivalents	18,945	28,764
Cash and investments segregated and on deposit for regulatory purposes	2,735	2,628
Receivables from brokerage clients — net	0	0
Held to maturity securities:	0	0
Bank loans – net	0	0
Other assets	0	0
Liabilities
Bank deposits	0	0
Payables to brokerage clients	0	0
Accrued expenses and other liabilities	0	0
Other short-term borrowings	0	0
Federal Home Loan Bank borrowings	0	0
Long-term debt	0	0
Portion at Other than Fair Value Measurement \| Level 1 \| Residential real estate \| First Mortgages
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 1 \| Residential real estate \| HELOCs
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 1 \| Pledged asset lines
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 1 \| Other
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 1 \| U.S. agency mortgage-backed securities
Assets
Held to maturity securities:	0	0
Portion at Other than Fair Value Measurement \| Level 2
Assets
Cash and cash equivalents	0	0
Cash and investments segregated and on deposit for regulatory purposes	9,345	8,810
Receivables from brokerage clients — net	71,118	68,629
Held to maturity securities:	142,340	147,091
Bank loans – net	37,837	37,575
Other assets	5,706	4,960
Liabilities
Bank deposits	269,460	289,953
Payables to brokerage clients	84,005	84,786
Accrued expenses and other liabilities	7,750	7,609
Other short-term borrowings	8,405	6,553
Federal Home Loan Bank borrowings	24,000	26,400
Long-term debt	21,727	25,000
Portion at Other than Fair Value Measurement \| Level 2 \| Residential real estate \| First Mortgages
Assets
Bank loans – net	23,198	23,226
Portion at Other than Fair Value Measurement \| Level 2 \| Residential real estate \| HELOCs
Assets
Bank loans – net	484	508
Portion at Other than Fair Value Measurement \| Level 2 \| Pledged asset lines
Assets
Bank loans – net	13,841	13,548
Portion at Other than Fair Value Measurement \| Level 2 \| Other
Assets
Bank loans – net	314	293
Portion at Other than Fair Value Measurement \| Level 2 \| U.S. agency mortgage-backed securities
Assets
Held to maturity securities:	142,340	147,091
Portion at Other than Fair Value Measurement \| Level 3
Assets
Cash and cash equivalents	0	0
Cash and investments segregated and on deposit for regulatory purposes	0	0
Receivables from brokerage clients — net	0	0
Held to maturity securities:	0	0
Bank loans – net	0	0
Other assets	0	0
Liabilities
Bank deposits	0	0
Payables to brokerage clients	0	0
Accrued expenses and other liabilities	0	0
Other short-term borrowings	0	0
Federal Home Loan Bank borrowings	0	0
Long-term debt	0	0
Portion at Other than Fair Value Measurement \| Level 3 \| Residential real estate \| First Mortgages
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 3 \| Residential real estate \| HELOCs
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 3 \| Pledged asset lines
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 3 \| Other
Assets
Bank loans – net	0	0
Portion at Other than Fair Value Measurement \| Level 3 \| U.S. agency mortgage-backed securities
Assets
Held to maturity securities:	$ 0	$ 0

Cash And Securities Segregated Under Federal And Other Regulations, Fair Value Disclosure

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Other Short-Term Borrowings, Fair Value

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Fair value portion of accrued expenses.

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Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Fair value portion of other assets.

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