Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flows from Operating Activities
Net income	$ 2,354	$ 1,889	$ 1,447
Adjustments to reconcile net income to net cash (used for) provided by operating activities:
Provision for loan losses	0	(5)	(11)
Share-based compensation	153	141	135
Depreciation and amortization	269	234	224
Provision (Benefit) for deferred income taxes	58	15	(7)
Premium amortization, net, on available for sale and held to maturity securities	342	266	162
Other	51	9	(4)
Net change in:
Cash and investments segregated and on deposit for regulatory purposes	7,035	(2,576)	1,183
Receivables from brokers, dealers, and clearing organizations	74	(147)	(108)
Receivables from brokerage clients	(3,428)	150	(1,652)
Other securities owned	(90)	84	(17)
Other assets	(177)	(93)	(98)
Payables to brokers, dealers, and clearing organizations	(1,148)	(181)	808
Payables to brokerage clients	(4,651)	2,709	(1,120)
Accrued expenses and other liabilities	421	167	304
Net cash provided by operating activities	1,263	2,662	1,246
Cash Flows from Investing Activities
Purchases of available for sale securities	(15,033)	(29,248)	(21,351)
Proceeds from sales of available for sale securities	8,617	5,537	2,424
Principal payments on available for sale securities	9,095	11,903	7,340
Purchases of held to maturity securities	(32,925)	(31,162)	(19,303)
Principal payments on held to maturity securities	11,627	5,747	3,540
Net increase in bank loans	(1,071)	(1,103)	(980)
Purchase of equipment, office facilities, and property	(400)	(346)	(266)
Purchases of Federal Home Loan Bank stock	(430)	(152)	0
Proceeds from sales of Federal Home Loan Bank stock	106	88	8
Other investing activities	(59)	(39)	(35)
Net cash used for investing activities	(20,473)	(38,775)	(28,623)
Cash Flows from Financing Activities
Net change in bank deposits	6,186	33,952	26,687
Net proceeds from short-term borrowings	15,000	0	0
Issuance of long-term debt	2,129	0	1,346
Repayment of long-term debt	(257)	(7)	(357)
Net proceeds from preferred stock offerings	492	1,316	581
Redemption of preferred stock	(485)	0	0
Dividends paid	(592)	(486)	(387)
Proceeds from stock options exercised and other	171	144	90
Other financing activities	(45)	44	32
Net cash provided by financing activities	22,599	34,963	27,992
Increase (Decrease) in Cash and Cash Equivalents	3,389	(1,150)	615
Cash and Cash Equivalents at Beginning of Year	10,828	11,978	11,363
Cash and Cash Equivalents at End of Year	14,217	10,828	11,978
Cash paid during the year for:
Interest	327	160	121
Income taxes	1,212	991	810
Non-cash investing activity:
Securities purchased during the year but settled after year end	$ 29	$ 0	$ 0