The Charles Schwab Corporation – Parent Company Only Financial Statements (Condensed Statements of Cash Flows) (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Flows from Operating Activities
Net income		$ 852	$ 951	$ 937	$ 964	$ 935	$ 923	$ 866	$ 783	$ 3,704	$ 3,507	$ 2,354
Adjustments to reconcile net income to net cash provided by operating activities:
Other										199	137	51
Net change in:
Other assets										(709)	(8)	(193)
Accrued expenses and other liabilities										(241)	613	(727)
Net cash provided by (used for) operating activities										9,325	12,456	(839)
Cash Flows from Investing Activities
Purchases of available for sale securities										(31,815)	(32,801)	(15,033)
Proceeds from sales of available for sale securities										24,495	115	8,617
Principal payments on available for sale securities										21,616	16,016	9,095
Other investing activities										(56)	(96)	(59)
Net cash provided by (used for) investing activities										11,964	(40,555)	(20,473)
Cash Flows from Financing Activities
Issuance of long-term debt										593	3,024	2,129
Repayment of long-term debt										0	(909)	(257)
Repurchases of common stock										(2,220)	(1,000)	0
Net proceeds from preferred stock offerings										0	0	492
Redemption of preferred stock										0	0	(485)
Dividends paid										(1,060)	(787)	(592)
Proceeds from stock options exercised										118	125	171
Net cash provided by (used for) financing activities										(13,939)	47,166	22,599
Cash and Cash Equivalents at Beginning of Year	[1]				27,938				14,217	27,938	14,217
Cash and Cash Equivalents at End of Year	[1]	29,345				27,938				29,345	27,938	14,217
Parent Company [Member]
Cash Flows from Operating Activities
Net income										3,704	3,507	2,354
Adjustments to reconcile net income to net cash provided by operating activities:
Dividends in excess of (equity in undistributed) earnings of subsidiaries										1,198	(2,590)	(1,479)
Other										9	13	5
Net change in:
Other assets										57	(5)	(27)
Accrued expenses and other liabilities										34	28	44
Net cash provided by (used for) operating activities										5,002	953	897
Cash Flows from Investing Activities
Due from (to) subsidiaries — net										(122)	408	(374)
Increase in investments in subsidiaries										(1,783)	(1,188)	(342)
Repayments (Advances) of subordinated loan to CS&Co										185	(185)	0
Purchases of available for sale securities										(1,141)	(1,751)	(201)
Proceeds from sales of available for sale securities										181	0	197
Principal payments on available for sale securities										994	573	0
Other investing activities										0	(5)	(6)
Net cash provided by (used for) investing activities										(1,686)	(2,148)	(726)
Cash Flows from Financing Activities
Issuance of long-term debt										593	3,024	2,129
Repayment of long-term debt										0	(900)	(250)
Repurchases of common stock										(2,220)	(1,000)	0
Net proceeds from preferred stock offerings										0	0	492
Redemption of preferred stock										0	0	(485)
Dividends paid										(1,060)	(787)	(592)
Proceeds from stock options exercised										118	125	171
Net cash provided by (used for) financing activities										(2,569)	462	1,465
Increase (Decrease) in Cash and Cash Equivalents										747	(733)	1,636
Cash and Cash Equivalents at Beginning of Year					$ 2,092				$ 2,825	2,092	2,825	1,189
Cash and Cash Equivalents at End of Year		$ 2,839				$ 2,092				$ 2,839	$ 2,092	$ 2,825

[1] For more information on the nature of restrictions on restricted cash and cash equivalents, see Note 21.