HSBC USA (HUSI+G) 10-Q 5 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 02, 2019
Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Registrant Name	HSBC USA INC /MD/
Entity Central Index Key	0000083246
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		714
Entity Current Reporting Status	Yes
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Zero Coupon Callable Accreting Notes due January 15, 2043 [Member]
Entity Information [Line Items]
Trading Symbol	HBA/43
Zero Coupon Callable Accreting Notes due January 29, 2043 [Member]
Entity Information [Line Items]
Trading Symbol	HBA/43A

CONSOLIDATED STATEMENT OF INCOM

CONSOLIDATED STATEMENT OF INCOME - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Interest income:
Loans		$ 743	$ 637	$ 1,459		$ 1,235
Securities		298	278	602		531
Trading securities		67	53	130		102
Short-term investments		173	157	349		315
Other		20	22	38		38
Total interest income		1,301	1,147	2,578		2,221
Interest expense:
Deposits		380	258	713		480
Short-term borrowings		68	43	130		76
Long-term debt		306	283	618		540
Other		7	8	15		18
Total interest expense		761	592	1,476		1,114
Net interest income		540	555	1,102		1,107
Provision for credit losses		46	(45)	104		(116)
Net interest income after provision for credit losses		494	600	998		1,223
Other revenues:
Other revenues		303	323	575		634
Trading revenue		123	192	256		355
Other securities gains, net		23	10	30		15
Gain (loss) on instruments designated at fair value and related derivatives		(17)	4	(26)		34
Other income (loss)		8	11	(3)		18
Total other revenues	[1]	436	537	826	[2]	1,050	[2]
Operating expenses:
Salaries and employee benefits		221	212	431		419
Support services from HSBC affiliates		411	405	791		816
Occupancy expense, net		48	45	93		88
Other expenses		94	124	209		745
Total operating expenses	[2]	774	786	1,524		2,068	[3]
Income before income tax		156	351	300		205
Income tax expense		35	82	70		174
Net income		121	269	230		31
Credit card fees, net [Member]
Other revenues:
Other revenues		18	15	30		26
Trust and investment management fees [Member]
Other revenues:
Other revenues		31	34	61		72
Other fees and commissions [Member]
Other revenues:
Other revenues		162	184	309		344
Servicing and other fees from HSBC affiliates [Member]
Other revenues:
Other revenues		$ 88	$ 87	$ 169		$ 186
[1]	See Note 15, "Business Segments," for a reconciliation of total other revenues on a U.S. GAAP basis to other operating income for each business segment under the Group Reporting Basis.
[2]	Represents adjustments associated with differences between U.S. GAAP and the Group Reporting Basis.
[3]	Represents differences in financial statement presentation between U.S. GAAP and the Group Reporting Basis.

CONSOLIDATED STATEMENT OF COMPR

CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 121	$ 269	$ 230	$ 31
Net change in unrealized gains (losses), net of tax:
Investment securities	220	(76)	399	(271)
Fair value option liabilities attributable to our own credit spread	7	129	(104)	141
Derivatives designated as cash flow hedges	5		19
Derivatives designated as cash flow hedges		10		12
Pension and post-retirement benefit plans	0	(1)	(3)	0
Total other comprehensive income (loss)	232	62	311	(118)
Comprehensive income (loss)	$ 353	$ 331	$ 541	$ (87)

CONSOLIDATED BALANCE SHEET

CONSOLIDATED BALANCE SHEET - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Assets:
Cash and due from banks		$ 1,196	$ 1,514
Interest bearing deposits with banks		11,736	15,700
Federal funds sold and securities purchased under agreements to resell		5,289	10,168
Trading assets (includes $7.4 billion and $2.5 billion of assets pledged to creditors at June 30, 2019 and December 31, 2018, respectively)		33,502	21,978
Securities available-for-sale (includes $2.3 billion and $0.8 billion of assets pledged to creditors at June 30, 2019 and December 31, 2018, respectively)		37,254	31,379
Securities held-to-maturity (fair value of $14.0 billion and $14.4 billion at June 30, 2019 and December 31, 2018, respectively)		13,927	14,670
Loans		72,478	68,978
Less – allowance for credit losses		613	541
Loans, net		71,865	68,437
Loans held for sale (includes $128 million and $109 million designated under fair value option at June 30, 2019 and December 31, 2018, respectively)		191	512
Properties and equipment, net		154	158
Goodwill		1,607	1,607
Other assets		7,342	6,325
Total assets	[1]	184,063	172,448
Domestic deposits:
Noninterest bearing		22,826	25,639
Interest bearing (includes $8.5 billion and $8.2 billion designated under fair value option at June 30, 2019 and December 31, 2018, respectively)		89,054	78,830
Foreign deposits:
Noninterest bearing		186	202
Interest bearing		4,895	6,274
Deposits held for sale		0	10
Total deposits		116,961	110,955
Short-term borrowings (includes $222 million and $560 million designated under fair value option at June 30, 2019 and December 31, 2018, respectively)		8,649	4,180
Long-term debt (includes $12.0 billion and $11.2 billion designated under fair value option at June 30, 2019 and December 31, 2018, respectively)		30,849	30,628
Total debt		156,459	145,763
Trading liabilities		4,026	3,643
Interest, taxes and other liabilities		4,944	2,536
Total liabilities	[1]	165,429	151,942
Equity
Preferred stock (no par value; 40,999,000 shares authorized; 1,265 shares issued and outstanding at both June 30, 2019 and December 31, 2018)		1,265	1,265
Common equity:
Common stock ($5 par; 150,000,000 shares authorized; 714 shares issued and outstanding at both June 30, 2019 and December 31, 2018)		0	0
Additional paid-in capital		15,734	18,136
Retained earnings		1,690	1,471
Accumulated other comprehensive loss		(55)	(366)
Total common equity		17,369	19,241
Total equity		18,634	20,506
Total liabilities and equity		$ 184,063	$ 172,448
[1]	The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at June 30, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 17, "Variable Interest Entities," for additional information. Assets: Other assets $98 million and $112 million. Total assets $98 million and $112 million respectively. Liabilities: Long-term debt $66 million and $66 million, Interest, taxes and other liabilities $32 million and $37 million. Total liabilities $98 million and $103 million, respectively.

CONSOLIDATED BALANCE SHEET (Par

CONSOLIDATED BALANCE SHEET (Parenthetical) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Assets pledged to creditors, trading assets	[1]	$ 7,429	$ 2,465
Securities held-to-maturity, fair value		$ 14,011	$ 14,443
Preferred stock, par value (usd per share)		$ 0	$ 0
Preferred stock, shares authorized (shares)		40,999,000	40,999,000
Preferred stock, shares issued (shares)		1,265	1,265
Preferred stock, shares outstanding (shares)		1,265	1,265
Common stock, par value (usd per share)		$ 5	$ 5
Common stock, shares authorized (shares)		150,000,000	150,000,000
Common stock, shares issued (shares)		714	714
Common stock, shares outstanding (shares)		714	714
Assets:
Loans		$ 11,736	$ 15,700
Other assets		7,342	6,325
Total assets	[2]	184,063	172,448
Short-term borrowings		8,649	4,180
Liabilities:
Long-term debt		30,849	30,628
Interest, taxes and other liabilities		4,944	2,536
Total liabilities	[2]	165,429	151,942
Variable interest entities [Member]
Assets:
Other assets		98	112
Total assets		98	112
Liabilities:
Long-term debt		66	66
Interest, taxes and other liabilities		32	37
Total liabilities		98	103
Loans Receivable [Member]
Loans Held-for-sale, designated under fair value option		128	109
Deposits [Member]
Deposits designated under fair value option		8,500	8,200
Short-term Borrowings [Member]
Short-term borrowings designated under fair value option		222	560
Long-term debt [Member]
Long-term debt designated under fair value option		12,000	11,200
Trading assets [Member]
Assets pledged to creditors, trading assets		7,402	2,464
Securities available-for-sale [Member]
Assets pledged to creditors, securities-available-for-sale		$ 2,290	$ 822
[1]	Trading assets are primarily pledged against liabilities associated with repurchase agreements.
[2]	The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at June 30, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 17, "Variable Interest Entities," for additional information. Assets: Other assets $98 million and $112 million. Total assets $98 million and $112 million respectively. Liabilities: Long-term debt $66 million and $66 million, Interest, taxes and other liabilities $32 million and $37 million. Total liabilities $98 million and $103 million, respectively.

CONSOLIDATED STATEMENT OF CHANG

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	As Previously Reported [Member]Retained Earnings [Member]	As Previously Reported [Member]Accumulated Other Comprehensive Loss [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-02 [Member]					$ 0
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-01, Equity Investments Previously Classified as Available-for-sale [Member]					(4)	$ 4
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-01, Equity Investments Previously Measured at Cost [Member]					10
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2018-02 [Member]					91	(91)
Balance at beginning of period at Dec. 31, 2017		$ 1,265
Balance at beginning of period at Dec. 31, 2017			$ 0	$ 18,130	1,227	(518)	$ 1,130	$ (431)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital to parent				0
Employee benefit plans				5
Net income (loss)	$ 31				31
Cash dividends declared on preferred stock					(37)
Other comprehensive income (loss), net of tax	(118)					(118)
Balance at end of period at Jun. 30, 2018	18,720		0	18,135	1,221	(636)
Balance at end of period at Jun. 30, 2018	19,985	1,265
Balance at beginning of period at Mar. 31, 2018		1,265
Balance at beginning of period at Mar. 31, 2018			0	18,127	989	(698)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee benefit plans				8
Net income (loss)	269				269
Cash dividends declared on preferred stock					(37)
Other comprehensive income (loss), net of tax	62					62
Balance at end of period at Jun. 30, 2018	18,720		0	18,135	1,221	(636)
Balance at end of period at Jun. 30, 2018	19,985	1,265
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-02 [Member]					27
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-01, Equity Investments Previously Classified as Available-for-sale [Member]					0	0
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-01, Equity Investments Previously Measured at Cost [Member]					0
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2018-02 [Member]					0	0
Balance at beginning of period at Dec. 31, 2018	20,506	1,265
Balance at beginning of period at Dec. 31, 2018	19,241		0	18,136	1,498	(366)	$ 1,471
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital to parent				(2,400)
Employee benefit plans				(2)
Net income (loss)	230				230
Cash dividends declared on preferred stock					(38)
Other comprehensive income (loss), net of tax	311					311
Balance at end of period at Jun. 30, 2019	17,369		0	15,734	1,690	(55)
Balance at end of period at Jun. 30, 2019	18,634	1,265
Balance at beginning of period at Mar. 31, 2019		1,265
Balance at beginning of period at Mar. 31, 2019			0	15,736	1,607	(287)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee benefit plans				(2)
Net income (loss)	121				121
Cash dividends declared on preferred stock					(38)
Other comprehensive income (loss), net of tax	232					232
Balance at end of period at Jun. 30, 2019	17,369		$ 0	$ 15,734	$ 1,690	$ (55)
Balance at end of period at Jun. 30, 2019	$ 18,634	$ 1,265

CONSOLIDATED STATEMENT OF CASH

CONSOLIDATED STATEMENT OF CASH FLOWS $ in Millions	6 Months Ended
	Jun. 30, 2019USD ($)		Jun. 30, 2018USD ($)
Cash flows from operating activities
Net income	$ 230		$ 31
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	30		(46)
Provision for credit losses	104		(116)
Net realized gains on securities available-for-sale	(30)		(15)
Net change in other assets and liabilities	2,306		639
Net change in loans held for sale:
Originations and purchases of loans held for sale	(1,160)		(1,311)
Sales and collections of loans held for sale	1,155		1,786
Net change in trading assets and liabilities	(11,141)		(11,023)
Lower of amortized cost or fair value adjustments on loans held for sale	0		(4)
Loss (gain) on instruments designated at fair value and related derivatives	26		(34)
Net cash used in operating activities	(8,480)		(10,093)
Cash flows from investing activities
Net change in federal funds sold and securities purchased under agreements to resell	4,879		22,442
Securities available-for-sale:
Purchases of securities available-for-sale	(12,608)		(5,410)
Proceeds from sales of securities available-for-sale	4,189		2,610
Proceeds from maturities of securities available-for-sale	3,832		1,594
Securities held-to-maturity:
Purchases of securities held-to-maturity	(384)		(2,344)
Proceeds from maturities of securities held-to-maturity	1,109		1,154
Change in loans:
Originations, net of collections	(3,654)		5,728
Loans sold to third parties	464		445
Net cash used for acquisitions of properties and equipment	(15)		(2)
Net outflows related to the sale of a portion of our Private Banking business	0		(378)
Other, net	52		(10)
Net cash provided by (used in) investing activities	(2,136)		25,829
Cash flows from financing activities
Net change in deposits	5,671		(3,757)
Debt:
Net change in short-term borrowings	4,469		1,741
Issuance of long-term debt	2,928		2,678
Repayment of long-term debt	(4,294)		(5,220)
Return of capital to parent	(2,400)		0
Other increases (decreases) in capital surplus	(2)		5
Dividends paid	(38)		(37)
Net cash provided by (used in) financing activities	6,334		(4,590)
Net change in cash and due from banks and interest bearing deposits with banks(1)	(4,282)	[1]	11,146	[1]
Cash and due from banks and interest bearing deposits with banks at beginning of period	17,214	[1]	12,272	[1]
Cash and and due from banks and interest bearing deposits with banks at end of period	12,932	[1]	23,418	[1]
Derivative Liabilities	$ 31,463
Adjustments for New Accounting Pronouncement [Member]
Debt:
Net change in cash and due from banks and interest bearing deposits with banks(1)			$ 11,331	[1]
[1]	As a result of adopting new accounting guidance in 2018, we changed our presentation of cash and cash equivalents to include cash and due from banks as well as interest bearing deposits with banks, which includes restricted cash. See Note 2, "Summary of Significant Accounting Policies and New Accounting Pronouncements," in our 2018 Form 10-K for further discussion. This resulted in an increase in cash provided by investing activities of $11,331 million during the six months ended June 30, 2018.

Organization and Presentation

Organization and Presentation	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Presentation	Organization and Presentation HSBC USA Inc. ("HSBC USA"), incorporated under the laws of Maryland, is a New York State based bank holding company and a wholly-owned subsidiary of HSBC North America Holdings Inc. ("HSBC North America"), which is an indirect wholly-owned subsidiary of HSBC Holdings plc ("HSBC" and, together with its subsidiaries, "HSBC Group"). The accompanying unaudited interim consolidated financial statements of HSBC USA and its subsidiaries (collectively "HUSI") have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X, as well as in accordance with predominant practices within the banking industry. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all normal and recurring adjustments considered necessary for a fair presentation of financial position, results of operations and cash flows for the interim periods have been made. HUSI may also be referred to in these notes to the consolidated financial statements as "we," "us" or "our." These unaudited interim consolidated financial statements should be read in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2018 (the "2018 Form 10-K"). Certain reclassifications have been made to prior period amounts to conform to the current period presentation. The preparation of financial statements in conformity with U.S. GAAP requires the use of estimates and assumptions that affect reported amounts and disclosures. Actual results could differ from those estimates. Interim results should not be considered indicative of results in future periods.

Trading Assets and Liabilities

Trading Assets and Liabilities	6 Months Ended
	Jun. 30, 2019
Trading Assets And Liabilities [Abstract]
Trading Assets and Liabilities	Trading Assets and Liabilities Trading assets and liabilities consisted of the following: June 30, 2019 December 31, 2018 (in millions) Trading assets: U.S. Treasury $ 10,620 $ 5,368 U.S. Government agency issued or guaranteed 19 111 U.S. Government sponsored enterprises 59 41 Asset-backed securities 192 208 Corporate and foreign bonds 12,925 10,562 Equity securities 2,747 751 Precious metals 3,895 1,889 Derivatives, net 3,045 3,048 Total trading assets $ 33,502 $ 21,978 Trading liabilities: Securities sold, not yet purchased $ 834 $ 738 Payables for precious metals 106 215 Derivatives, net 3,086 2,690 Total trading liabilities $ 4,026 $ 3,643 At June 30, 2019 and December 31, 2018 , the fair value of derivatives included in trading assets is net of $2,638 million and $2,013 million , respectively, relating to amounts recognized for the obligation to return cash collateral received under master netting agreements with derivative counterparties. At June 30, 2019 and December 31, 2018 , the fair value of derivatives included in trading liabilities is net of $3,627 million and $3,458 million , respectively, relating to amounts recognized for the right to reclaim cash collateral paid under master netting agreements with derivative counterparties. See Note 9, "Derivative Financial Instruments," for further information on our trading derivatives and related collateral.

Securities

Securities	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Securities	Securities Our securities available-for-sale and securities held-to-maturity portfolios consisted of the following: June 30, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) Securities available-for-sale: U.S. Treasury $ 16,942 $ 148 $ (264 ) $ 16,826 U.S. Government sponsored enterprises: Mortgage-backed securities 4,777 76 (26 ) 4,827 Collateralized mortgage obligations 684 2 (5 ) 681 Direct agency obligations 2,751 29 (1 ) 2,779 U.S. Government agency issued or guaranteed: Mortgage-backed securities 7,834 24 (61 ) 7,797 Collateralized mortgage obligations 964 10 (7 ) 967 Direct agency obligations 252 2 (1 ) 253 Asset-backed securities collateralized by: Home equity 39 — (3 ) 36 Other 108 5 — 113 Foreign debt securities (1) 2,971 4 — 2,975 Total available-for-sale securities $ 37,322 $ 300 $ (368 ) $ 37,254 Securities held-to-maturity: U.S. Government sponsored enterprises: Mortgage-backed securities $ 1,843 $ 15 $ (3 ) $ 1,855 Collateralized mortgage obligations 1,718 46 (7 ) 1,757 U.S. Government agency issued or guaranteed: Mortgage-backed securities 2,179 6 (2 ) 2,183 Collateralized mortgage obligations 8,174 67 (39 ) 8,202 Obligations of U.S. states and political subdivisions 11 1 — 12 Asset-backed securities collateralized by residential mortgages 2 — — 2 Total held-to-maturity securities $ 13,927 $ 135 $ (51 ) $ 14,011 December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) Securities available-for-sale: U.S. Treasury $ 13,549 $ 106 $ (365 ) $ 13,290 U.S. Government sponsored enterprises: Mortgage-backed securities 5,541 6 (154 ) 5,393 Collateralized mortgage obligations 686 1 (35 ) 652 Direct agency obligations 2,831 37 (2 ) 2,866 U.S. Government agency issued or guaranteed: Mortgage-backed securities 4,442 1 (171 ) 4,272 Collateralized mortgage obligations 1,140 9 (29 ) 1,120 Direct agency obligations 295 9 — 304 Asset-backed securities collateralized by: Home equity 44 — (2 ) 42 Other 102 5 — 107 Foreign debt securities (1) 3,330 3 — 3,333 Total available-for-sale securities $ 31,960 $ 177 $ (758 ) $ 31,379 Securities held-to-maturity: U.S. Government sponsored enterprises: Mortgage-backed securities $ 1,812 $ 1 $ (34 ) $ 1,779 Collateralized mortgage obligations 1,878 34 (26 ) 1,886 U.S. Government agency issued or guaranteed: Mortgage-backed securities 2,104 2 (63 ) 2,043 Collateralized mortgage obligations 8,863 35 (176 ) 8,722 Obligations of U.S. states and political subdivisions 11 — — 11 Asset-backed securities collateralized by residential mortgages 2 — — 2 Total held-to-maturity securities $ 14,670 $ 72 $ (299 ) $ 14,443 (1) Foreign debt securities represent public sector entity, bank or corporate debt. Net unrealized losses were lower within the available-for-sale portfolio as compared with December 31, 2018 due primarily to decreasing yields on U.S. Government sponsored mortgage-backed, U.S. Government agency mortgage-backed, and U.S. Treasury securities. The following table summarizes gross unrealized losses and related fair values at June 30, 2019 and December 31, 2018 classified as to the length of time the losses have existed: One Year or Less Greater Than One Year June 30, 2019 Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment (dollars are in millions) Securities available-for-sale: U.S. Treasury 17 $ (31 ) $ 3,652 32 $ (233 ) $ 6,030 U.S. Government sponsored enterprises 1 — 252 122 (32 ) 2,678 U.S. Government agency issued or guaranteed 2 (6 ) 177 59 (63 ) 4,093 Asset-backed securities — — — 5 (3 ) 36 Foreign debt securities 18 — 1,440 — — — Securities available-for-sale 38 $ (37 ) $ 5,521 218 $ (331 ) $ 12,837 Securities held-to-maturity: U.S. Government sponsored enterprises 12 $ — $ 3 301 $ (10 ) $ 1,210 U.S. Government agency issued or guaranteed 32 — 187 386 (41 ) 4,769 Obligations of U.S. states and political subdivisions — — — 1 — — Securities held-to-maturity 44 $ — $ 190 688 $ (51 ) $ 5,979 One Year or Less Greater Than One Year December 31, 2018 Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment (dollars are in millions) Securities available-for-sale: U.S. Treasury 8 $ (12 ) $ 1,013 41 $ (353 ) $ 8,828 U.S. Government sponsored enterprises 55 (6 ) 538 159 (185 ) 3,698 U.S. Government agency issued or guaranteed 8 (2 ) 106 72 (198 ) 4,825 Asset-backed securities 1 — — 4 (2 ) 42 Foreign debt securities 16 — 1,724 — — — Securities available-for-sale 88 $ (20 ) $ 3,381 276 $ (738 ) $ 17,393 Securities held-to-maturity: U.S. Government sponsored enterprises 103 $ (8 ) $ 684 511 $ (52 ) $ 1,739 U.S. Government agency issued or guaranteed 111 (14 ) 769 491 (225 ) 7,372 Obligations of U.S. states and political subdivisions 1 — — 1 — — Securities held-to-maturity 215 $ (22 ) $ 1,453 1,003 $ (277 ) $ 9,111 Although the fair value of a particular security may be below its amortized cost, it does not necessarily result in a credit loss and hence an other-than-temporary impairment. The decline in fair value may be caused by, among other things, the illiquidity of the market. We have reviewed the securities for which there is an unrealized loss for other-than-temporary impairment in accordance with our accounting policies, discussed further below. At June 30, 2019 and December 31, 2018 , we do not consider any of our debt securities to be other-than-temporarily impaired as we expect to recover their amortized cost basis and we neither intend nor expect to be required to sell these securities prior to recovery, even if that equates to holding securities until their individual maturities. However, other-than-temporary impairments may occur in future periods if the credit quality of the securities deteriorates. Other-Than-Temporary Impairment On a quarterly basis, we perform an assessment to determine whether there have been any events or economic circumstances to indicate that a debt security with an unrealized loss has suffered other-than-temporary impairment. A debt security is considered impaired if its fair value is less than its amortized cost basis at the reporting date. If impaired, we assess whether the impairment is other-than-temporary. If we intend to sell the debt security or if it is more-likely-than-not that we will be required to sell the debt security before the recovery of its amortized cost basis, the impairment is considered other-than-temporary and the unrealized loss is recorded in earnings. An impairment is also considered other-than-temporary if a credit loss exists (i.e., the present value of the expected future cash flows is less than the amortized cost basis of the debt security). In the event a credit loss exists, the credit loss component of an other-than-temporary impairment is recorded in earnings while the remaining portion of the impairment loss attributable to factors other than credit loss is recognized, net of tax, in other comprehensive income (loss). For all securities held in the available-for-sale or held-to-maturity portfolios for which unrealized losses attributed to factors other than credit existed, we do not have the intention to sell and believe we will not be required to sell the securities for contractual, regulatory or liquidity reasons as of the reporting date. For a complete description of the factors considered when analyzing debt securities for impairments, see Note 4, "Securities," in our 2018 Form 10-K. There have been no material changes in our process for assessing impairment during 2019. During the three and six months ended June 30, 2019 and 2018 , none of our debt securities were determined to have other-than-temporary impairment, as such, there were no other-than-temporary impairment losses recognized related to credit loss. Other securities gains, net The following table summarizes realized gains and losses on investment securities transactions attributable to available-for-sale securities: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Gross realized gains $ 27 $ 21 $ 43 $ 30 Gross realized losses (4 ) (11 ) (13 ) (15 ) Net realized gains $ 23 $ 10 $ 30 $ 15 Contractual Maturities and Yields The following table summarizes the amortized cost and fair values of securities available-for-sale and securities held-to-maturity at June 30, 2019 by contractual maturity. Expected maturities differ from contractual maturities because borrowers have the right to prepay obligations without prepayment penalties in certain cases. The table below also reflects the distribution of maturities of debt securities held at June 30, 2019 , together with the approximate yield of the portfolio. The yields shown are calculated by dividing annualized interest income, including the accretion of discounts and the amortization of premiums, by the amortized cost of securities outstanding at June 30, 2019 . Within One Year After One But Within Five Years After Five But Within Ten Years After Ten Years Amount Yield Amount Yield Amount Yield Amount Yield (dollars are in millions) Available-for-sale: U.S. Treasury $ 199 2.22 % $ 7,760 1.81 % $ 5,967 2.05 % $ 3,016 2.80 % U.S. Government sponsored enterprises 1,047 2.99 1,168 2.83 2,218 2.74 3,779 3.00 U.S. Government agency issued or guaranteed — — 81 2.21 1 4.33 8,968 2.72 Asset-backed securities — — — — 58 5.21 89 3.90 Foreign debt securities 1,552 .00 1,419 2.56 — — — — Total amortized cost $ 2,798 1.27 % $ 10,428 2.03 % $ 8,244 2.26 % $ 15,852 2.81 % Total fair value $ 2,801 $ 10,445 $ 8,191 $ 15,817 Held-to-maturity: U.S. Government sponsored enterprises $ 50 2.22 % $ 376 2.72 % $ 269 2.45 % $ 2,866 3.04 % U.S. Government agency issued or guaranteed — — 13 3.94 22 3.69 10,318 2.68 Obligations of U.S. states and political subdivisions 1 4.75 5 3.46 5 4.20 — — Asset-backed securities — — — — — — 2 7.83 Total amortized cost $ 51 2.27 % $ 394 2.77 % $ 296 2.57 % $ 13,186 2.76 % Total fair value $ 51 $ 399 $ 298 $ 13,263 Equity Securities Equity securities that are not classified as trading and are included in other assets consisted of the following: June 30, 2019 December 31, 2018 (in millions) Equity securities carried at fair value $ 302 $ 278 Equity securities without readily determinable fair values 9 7 On a quarterly basis, we perform an assessment to determine whether any equity securities without readily determinable fair values are impaired. In the event an equity security is deemed impaired, the security is written down to fair value with impairment recorded in earnings. At June 30, 2019 and December 31, 2018 , none of our equity securities without readily determinable fair values were determined to be impaired. Also included in other assets were investments in Federal Home Loan Bank ("FHLB") stock and Federal Reserve Bank stock of $155 million and $559 million , respectively, at June 30, 2019 and $156 million and $631 million , respectively, at December 31, 2018 .

Loans

Loans	6 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Loans	Loans Loans consisted of the following: June 30, 2019 December 31, 2018 (in millions) Commercial loans: Real estate, including construction $ 11,704 $ 11,344 Business and corporate banking 14,310 13,066 Global banking (1) 20,896 20,167 Other commercial (2) 5,835 4,765 Total commercial 52,745 49,342 Consumer loans: Residential mortgages 17,421 17,383 Home equity mortgages 911 982 Credit cards 1,129 1,019 Other consumer 272 252 Total consumer 19,733 19,636 Total loans $ 72,478 $ 68,978 (1) Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers. (2) Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018 , respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates. Net deferred origination costs totaled $77 million at both June 30, 2019 and December 31, 2018 . At June 30, 2019 and December 31, 2018 , we had a net unamortized premium on our loans of $1 million and $11 million , respectively. Aging Analysis of Past Due Loans The following table summarizes the past due status of our loans, excluding loans held for sale, at June 30, 2019 and December 31, 2018 . The aging of past due amounts is determined based on the contractual delinquency status of payments under the loan. An account is generally considered to be contractually delinquent when payments have not been made in accordance with the loan terms. Delinquency status is affected by customer account management policies and practices such as re-age, which results in the re-setting of the contractual delinquency status to current. Past Due Total Past Due 30 Days or More At June 30, 2019 30 - 89 Days 90+ Days Current (1) Total Loans (in millions) Commercial loans: Real estate, including construction $ 10 $ 1 $ 11 $ 11,693 $ 11,704 Business and corporate banking 10 19 29 14,281 14,310 Global banking — — — 20,896 20,896 Other commercial — — — 5,835 5,835 Total commercial 20 20 40 52,705 52,745 Consumer loans: Residential mortgages 341 257 598 16,823 17,421 Home equity mortgages 12 25 37 874 911 Credit cards 16 18 34 1,095 1,129 Other consumer 6 4 10 262 272 Total consumer 375 304 679 19,054 19,733 Total loans $ 395 $ 324 $ 719 $ 71,759 $ 72,478 Past Due Total Past Due 30 Days or More At December 31, 2018 30 - 89 Days 90+ Days Current (1) Total Loans (in millions) Commercial loans: Real estate, including construction $ 76 $ 3 $ 79 $ 11,265 $ 11,344 Business and corporate banking 79 38 117 12,949 13,066 Global banking — — — 20,167 20,167 Other commercial 15 — 15 4,750 4,765 Total commercial 170 41 211 49,131 49,342 Consumer loans: Residential mortgages 469 254 723 16,660 17,383 Home equity mortgages 14 27 41 941 982 Credit cards 13 14 27 992 1,019 Other consumer 5 5 10 242 252 Total consumer 501 300 801 18,835 19,636 Total loans $ 671 $ 341 $ 1,012 $ 67,966 $ 68,978 (1) Loans less than 30 days past due are presented as current. Nonaccrual Loans Nonaccrual loans, including nonaccrual loans held for sale, and accruing loans 90 days or more delinquent consisted of the following: June 30, 2019 December 31, 2018 (in millions) Nonaccrual loans: Commercial: Real estate, including construction $ 7 $ 7 Business and corporate banking 90 70 Global banking 53 65 Other commercial — 1 Commercial nonaccrual loans held for sale 22 — Total commercial 172 143 Consumer: Residential mortgages (1)(2)(3) 370 341 Home equity mortgages (1)(2) 48 55 Consumer nonaccrual loans held for sale 1 1 Total consumer 419 397 Total nonaccruing loans 591 540 Accruing loans contractually past due 90 days or more: Commercial: Business and corporate banking 1 1 Total commercial 1 1 Consumer: Credit cards 18 14 Other consumer 4 6 Total consumer 22 20 Total accruing loans contractually past due 90 days or more 23 21 Total nonperforming loans $ 614 $ 561 (1) At June 30, 2019 and December 31, 2018 , nonaccrual consumer mortgage loans held for investment include $267 million and $289 million , respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell. (2) Nonaccrual consumer mortgage loans held for investment include all loans which are 90 or more days contractually delinquent as well as loans discharged under Chapter 7 bankruptcy and not re-affirmed and second lien loans where the first lien loan that we own or service is 90 or more days contractually delinquent. (3) Nonaccrual consumer mortgage loans for all periods does not include guaranteed loans purchased from the Government National Mortgage Association. Repayment of these loans is predominantly insured by the Federal Housing Administration and as such, these loans have different risk characteristics from the rest of our consumer loan portfolio. The following table provides additional information on our nonaccrual loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest income that would have been recorded if the nonaccrual loans had been current in accordance with contractual terms during the period $ 7 $ 13 $ 16 $ 27 Interest income that was recorded on nonaccrual loans and included in interest income during the period 3 6 6 15 Impaired Loans A loan is considered to be impaired when it is deemed probable that not all principal and interest amounts due according to the contractual terms of the loan agreement will be collected. Probable losses from impaired loans are quantified and recorded as a component of the overall allowance for credit losses. Commercial and consumer loans for which we have modified the loan terms as part of a troubled debt restructuring are considered to be impaired loans. Additionally, commercial loans in nonaccrual status, or that have been partially charged-off or assigned a specific allowance for credit losses are also considered impaired loans. Troubled debt restructurings TDR Loans represent loans for which the original contractual terms have been modified to provide for terms that are less than what we would be willing to accept for new loans with comparable risk because of deterioration in the borrower's financial condition. Modifications for consumer or commercial loans may include changes to one or more terms of the loan, including, but not limited to, a change in interest rate, extension of the amortization period, reduction in payment amount and partial forgiveness or deferment of principal, accrued interest or other loan covenants. A substantial amount of our modifications involve interest rate reductions on consumer loans, which lower the amount of interest income we are contractually entitled to receive in future periods. Through lowering the interest rate and other loan term changes, we believe we are able to increase the amount of cash flow that will ultimately be collected from the loan, given the borrower's financial condition. TDR Loans are reserved for primarily based on the present value of expected future cash flows, discounted at the loan's original effective interest rate, which generally results in a higher reserve requirement for these loans, or as a practical expedient, the fair value of the collateral if the loan is collateral dependent or, for commercial loans, the observable market price if the loan is traded in the market. Once a consumer loan is classified as a TDR Loan, it continues to be reported as such until it is paid off or charged-off. For commercial loans, if subsequent performance is in accordance with the new terms and such terms reflect current market rates at the time of restructure, they will no longer be reported as a TDR Loan beginning in the year after restructuring. During the second quarter of 2019, a $12 million commercial loan met this criterion and was removed from TDR Loan classification. There were no loans removed from TDR Loan classification during the prior year periods. The following table presents information about loans which were modified during the three and six months ended June 30, 2019 and 2018 and as a result of this action became classified as TDR Loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Residential mortgages $ — $ 12 $ 1 $ 17 Home equity mortgages — 1 — 3 Credit cards 1 1 2 2 Total consumer $ 1 $ 14 $ 3 $ 22 During the three and six months ended June 30, 2019 and 2018 , there were no commercial loans which were modified and as a result of this action became classified as TDR Loans. The weighted-average contractual rate reduction for consumer loans which became classified as TDR Loans during the three and six months ended June 30, 2019 was 3.88 percent and 1.45 percent , respectively, compared with 1.58 percent and 2.02 percent during the three and six months ended June 30, 2018 , respectively. The following table presents information about our TDR Loans and the related allowance for credit losses for TDR Loans: June 30, 2019 December 31, 2018 Carrying Value Unpaid Principal Balance Carrying Value Unpaid Principal Balance (in millions) TDR Loans: (1)(2) Commercial loans: Business and corporate banking $ 59 $ 74 $ 68 $ 86 Global banking 84 92 113 119 Total commercial (3) 143 166 181 205 Consumer loans: Residential mortgages (4) 608 694 640 730 Home equity mortgages (4) 33 62 35 65 Credit cards 4 4 3 4 Total consumer 645 760 678 799 Total TDR Loans (5) $ 788 $ 926 $ 859 $ 1,004 Allowance for credit losses for TDR Loans: (6) Commercial loans: Business and corporate banking $ 12 $ 12 Global banking — — Total commercial 12 12 Consumer loans: Residential mortgages 3 3 Home equity mortgages — 1 Credit cards 1 1 Total consumer 4 5 Total allowance for credit losses for TDR Loans $ 16 $ 17 (1) TDR Loans are considered to be impaired loans. For commercial loans, impaired loans include other loans in addition to TDR Loans which totaled $63 million and $54 million at June 30, 2019 and December 31, 2018 , respectively. (2) The carrying value of TDR Loans includes basis adjustments on the loans, such as partial charge-offs. (3) Additional commitments to lend to commercial borrowers whose loans have been modified in TDR Loans totaled $226 million and $151 million at June 30, 2019 and December 31, 2018 , respectively. (4) At June 30, 2019 and December 31, 2018 , the carrying value of consumer mortgage TDR Loans held for investment includes $584 million and $615 million , respectively, of loans that are recorded at the lower of amortized cost or fair value of the collateral less cost to sell. (5) At June 30, 2019 and December 31, 2018 , the carrying value of TDR Loans includes $256 million and $286 million , respectively, of loans which are classified as nonaccrual. (6) Included in the allowance for credit losses. The following table presents information about average TDR Loans and interest income recognized on TDR Loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Average balance of TDR Loans: Commercial loans: Business and corporate banking $ 65 $ 137 $ 66 $ 156 Global banking 82 110 92 132 Total commercial 147 247 158 288 Consumer loans: Residential mortgages 615 664 621 670 Home equity mortgages 33 35 34 34 Credit cards 4 4 4 4 Total consumer 652 703 659 708 Total average balance of TDR Loans $ 799 $ 950 $ 817 $ 996 Interest income recognized on TDR Loans: Commercial loans: Business and corporate banking $ 1 $ — $ 2 $ 4 Global banking — 1 1 2 Total commercial 1 1 3 6 Consumer loans: Residential mortgages 6 7 13 14 Home equity mortgages 1 1 1 1 Total consumer 7 8 14 15 Total interest income recognized on TDR Loans $ 8 $ 9 $ 17 $ 21 The following table presents consumer loans which were classified as TDR Loans during the previous 12 months which subsequently became 60 days or greater contractually delinquent during the three and six months ended June 30, 2019 and 2018 : Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Consumer loans: Residential mortgages $ 1 $ — $ 3 $ 2 Home equity mortgages — 1 — 2 Total consumer $ 1 $ 1 $ 3 $ 4 During the three and six months ended June 30, 2019 and 2018 , there were no commercial TDR Loans which were classified as TDR Loans during the previous 12 months which subsequently became 90 days or greater contractually delinquent. Impaired commercial loans The following table presents information about impaired commercial loans and the related impairment reserve: Amount with Impairment Reserves (1) Amount without Impairment Reserves (1) Total Impaired Commercial Loans (1)(2) Impairment Reserve Unpaid Principal Balance (in millions) At June 30, 2019 Real estate, including construction $ 3 $ 1 $ 4 $ 2 $ 4 Business and corporate banking 46 55 101 21 110 Global banking — 101 101 — 111 Total commercial $ 49 $ 157 $ 206 $ 23 $ 225 At December 31, 2018 Real estate, including construction $ 3 $ 3 $ 6 $ 1 $ 6 Business and corporate banking 58 37 95 18 109 Global banking — 133 133 — 140 Other commercial — 1 1 — 1 Total commercial $ 61 $ 174 $ 235 $ 19 $ 256 (1) Reflects the carrying value of impaired commercial loans and includes basis adjustments on the loans, such as partial charge-offs. (2) Includes impaired commercial loans that are also considered TDR Loans which totaled $143 million and $181 million at June 30, 2019 and December 31, 2018 , respectively. The following table presents information about average impaired commercial loans and interest income recognized on impaired commercial loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Average balance of impaired commercial loans: Real estate, including construction $ 4 $ 12 $ 5 $ 11 Business and corporate banking 105 272 101 264 Global banking 100 248 111 311 Total average balance of impaired commercial loans $ 209 $ 532 $ 217 $ 586 Interest income recognized on impaired commercial loans: Business and corporate banking $ 2 $ 1 $ 3 $ 6 Global banking — 1 1 2 Total interest income recognized on impaired commercial loans $ 2 $ 2 $ 4 $ 8 Commercial Loan Credit Quality Indicators The following credit quality indicators are monitored for our commercial loan portfolio: Criticized loans Criticized loan classifications presented in the table below are determined by the assignment of various criticized facility grades based on the risk rating standards of our regulator. The following table summarizes criticized commercial loans: Special Mention Substandard Doubtful Total (in millions) At June 30, 2019 Real estate, including construction $ 784 $ 151 $ 1 $ 936 Business and corporate banking 282 441 27 750 Global banking 243 276 — 519 Total commercial $ 1,309 $ 868 $ 28 $ 2,205 At December 31, 2018 Real estate, including construction $ 452 $ 93 $ 4 $ 549 Business and corporate banking 193 314 15 522 Global banking 262 277 — 539 Other commercial — 1 — 1 Total commercial $ 907 $ 685 $ 19 $ 1,611 Nonperforming The following table summarizes the status of our commercial loan portfolio, excluding loans held for sale: Performing Loans Nonaccrual Loans Accruing Loans Contractually Past Due 90 days or More Total (in millions) At June 30, 2019 Real estate, including construction $ 11,697 $ 7 $ — $ 11,704 Business and corporate banking 14,219 90 1 14,310 Global banking 20,843 53 — 20,896 Other commercial 5,835 — — 5,835 Total commercial $ 52,594 $ 150 $ 1 $ 52,745 At December 31, 2018 Real estate, including construction $ 11,337 $ 7 $ — $ 11,344 Business and corporate banking 12,995 70 1 13,066 Global banking 20,102 65 — 20,167 Other commercial 4,764 1 — 4,765 Total commercial $ 49,198 $ 143 $ 1 $ 49,342 Credit risk profile The following table shows the credit risk profile of our commercial loan portfolio: Investment Grade (1) Non-Investment Grade Total (in millions) At June 30, 2019 Real estate, including construction $ 6,807 $ 4,897 $ 11,704 Business and corporate banking 5,969 8,341 14,310 Global banking 14,860 6,036 20,896 Other commercial 5,158 677 5,835 Total commercial $ 32,794 $ 19,951 $ 52,745 At December 31, 2018 Real estate, including construction $ 6,769 $ 4,575 $ 11,344 Business and corporate banking 5,674 7,392 13,066 Global banking 14,764 5,403 20,167 Other commercial 3,990 775 4,765 Total commercial $ 31,197 $ 18,145 $ 49,342 (1) Investment grade includes commercial loans with credit ratings of at least BBB- or above or the equivalent based on our internal credit rating system. Consumer Loan Credit Quality Indicators The following credit quality indicators are utilized for our consumer loan portfolio: Delinquency The following table summarizes dollars of two-months-and-over contractual delinquency and as a percent of total loans and loans held for sale ("delinquency ratio") for our consumer loan portfolio: June 30, 2019 December 31, 2018 Delinquent Loans Delinquency Ratio Delinquent Loans Delinquency Ratio (dollars are in millions) Residential mortgages (1)(2) $ 319 1.83 % $ 347 1.99 % Home equity mortgages (1)(2) 27 2.96 30 3.05 Credit cards 25 2.21 20 1.96 Other consumer 6 2.21 8 2.62 Total consumer $ 377 1.91 % $ 405 2.05 % (1) At June 30, 2019 and December 31, 2018 , consumer mortgage loan delinquency includes $239 million and $254 million , respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell, including $1 million and $1 million , respectively, relating to loans held for sale. (2) At June 30, 2019 and December 31, 2018 , consumer mortgage loans and loans held for sale include $146 million and $125 million , respectively, of loans that were in the process of foreclosure. Nonperforming The following table summarizes the status of our consumer loan portfolio, excluding loans held for sale: Performing Loans Nonaccrual Loans Accruing Loans Contractually Past Due 90 days or More Total (in millions) At June 30, 2019 Residential mortgages $ 17,051 $ 370 $ — $ 17,421 Home equity mortgages 863 48 — 911 Credit cards 1,111 — 18 1,129 Other consumer 268 — 4 272 Total consumer $ 19,293 $ 418 $ 22 $ 19,733 At December 31, 2018 Residential mortgages $ 17,042 $ 341 $ — $ 17,383 Home equity mortgages 927 55 — 982 Credit cards 1,005 — 14 1,019 Other consumer 246 — 6 252 Total consumer $ 19,220 $ 396 $ 20 $ 19,636 Troubled debt restructurings See discussion of impaired loans above for further details on this credit quality indicator. Concentration of Credit Risk At June 30, 2019 and December 31, 2018 , our loan portfolios included interest-only residential mortgage and home equity mortgage loans totaling $3,254 million and $3,208 million , respectively. An interest-only residential mortgage loan allows a customer to pay the interest-only portion of the monthly payment for a period of time which results in lower payments during the initial loan period. However, subsequent events affecting a customer's financial position could affect the ability of customers to repay the loan in the future when the principal payments are required which increases the credit risk of this loan type.

Allowance for Credit Losses

Allowance for Credit Losses	6 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Allowance for Credit Losses	Allowance for Credit Losses The following table summarizes the changes in the allowance for credit losses by product and the related loan balance by product during the three and six months ended June 30, 2019 and 2018 : Commercial Consumer Real Estate, including Construction Business Global Other Residential Home Credit Other Total (in millions) Three Months Ended June 30, 2019 Allowance for credit losses – beginning of period $ 119 $ 239 $ 122 $ 15 $ 10 $ 8 $ 63 $ 7 $ 583 Provision charged (credited) to income 30 13 (9 ) (6 ) 1 (1 ) 19 (1 ) 46 Charge-offs — (2 ) (3 ) — (3 ) (1 ) (12 ) (2 ) (23 ) Recoveries — 1 — — 3 1 1 1 7 Net (charge-offs) recoveries — (1 ) (3 ) — — — (11 ) (1 ) (16 ) Allowance for credit losses – end of period $ 149 $ 251 $ 110 $ 9 $ 11 $ 7 $ 71 $ 5 $ 613 Three Months Ended June 30, 2018 Allowance for credit losses – beginning of period $ 92 $ 207 $ 211 $ 19 $ 18 $ 10 $ 38 $ 4 $ 599 Provision charged (credited) to income (4 ) (27 ) (25 ) — (4 ) — 13 2 (45 ) Charge-offs — (6 ) (32 ) — (1 ) (2 ) (7 ) (2 ) (50 ) Recoveries — 22 — — 2 1 1 1 27 Net (charge-offs) recoveries — 16 (32 ) — 1 (1 ) (6 ) (1 ) (23 ) Allowance for credit losses – end of period $ 88 $ 196 $ 154 $ 19 $ 15 $ 9 $ 45 $ 5 $ 531 Six Months Ended June 30, 2019 Allowance for credit losses – beginning of period $ 116 $ 219 $ 108 $ 15 $ 13 $ 7 $ 58 $ 5 $ 541 Provision charged (credited) to income 33 35 5 (6 ) — — 35 2 104 Charge-offs — (4 ) (3 ) — (7 ) (2 ) (25 ) (3 ) (44 ) Recoveries — 1 — — 5 2 3 1 12 Net (charge-offs) recoveries — (3 ) (3 ) — (2 ) — (22 ) (2 ) (32 ) Allowance for credit losses – end of period $ 149 $ 251 $ 110 $ 9 $ 11 $ 7 $ 71 $ 5 $ 613 Ending balance: collectively evaluated for impairment $ 147 $ 230 $ 110 $ 9 $ 8 $ 7 $ 70 $ 5 $ 586 Ending balance: individually evaluated for impairment 2 21 — — 3 — 1 — 27 Total allowance for credit losses $ 149 $ 251 $ 110 $ 9 $ 11 $ 7 $ 71 $ 5 $ 613 Loans: Collectively evaluated for impairment (1) $ 11,700 $ 14,209 $ 20,795 $ 5,835 $ 16,559 $ 854 $ 1,125 $ 272 $ 71,349 Individually evaluated for impairment (2) 4 101 101 — 53 4 4 — 267 Loans carried at lower of amortized cost or fair value less cost to sell — — — — 809 53 — — 862 Total loans $ 11,704 $ 14,310 $ 20,896 $ 5,835 $ 17,421 $ 911 $ 1,129 $ 272 $ 72,478 Commercial Consumer Real Estate, including Construction Business Global Other Residential Home Credit Other Total (in millions) Six Months Ended June 30, 2018 Allowance for credit losses – beginning of period $ 82 $ 244 $ 264 $ 18 $ 25 $ 11 $ 32 $ 5 $ 681 Provision charged (credited) to income 6 (61 ) (74 ) 1 (14 ) (1 ) 25 2 (116 ) Charge-offs — (31 ) (37 ) — (1 ) (4 ) (15 ) (3 ) (91 ) Recoveries — 44 1 — 5 3 3 1 57 Net (charge-offs) recoveries — 13 (36 ) — 4 (1 ) (12 ) (2 ) (34 ) Allowance for credit losses – end of period $ 88 $ 196 $ 154 $ 19 $ 15 $ 9 $ 45 $ 5 $ 531 Ending balance: collectively evaluated for impairment $ 87 $ 169 $ 139 $ 19 $ 10 $ 8 $ 44 $ 5 $ 481 Ending balance: individually evaluated for impairment 1 27 15 — 5 1 1 — 50 Total allowance for credit losses $ 88 $ 196 $ 154 $ 19 $ 15 $ 9 $ 45 $ 5 $ 531 Loans: Collectively evaluated for impairment (1) $ 11,234 $ 11,852 $ 18,704 $ 4,612 $ 16,397 $ 1,019 $ 837 $ 303 $ 64,958 Individually evaluated for impairment (2) 11 257 173 — 59 3 4 — 507 Loans carried at lower of amortized cost or fair value less cost to sell — — — — 870 64 — — 934 Total loans $ 11,245 $ 12,109 $ 18,877 $ 4,612 $ 17,326 $ 1,086 $ 841 $ 303 $ 66,399 (1) Other commercial includes loans to HSBC affiliates totaling $3,096 million and $1,895 million at June 30, 2019 and 2018 , respectively, for which we do not carry an associated allowance for credit losses. (2) For consumer loans and certain small business loans, these amounts represent TDR Loans for which we evaluate reserves using a discounted cash flow methodology. Each loan is individually identified as a TDR Loan and then grouped together with other TDR Loans with similar characteristics. The discounted cash flow analysis is then applied to these groups of TDR Loans. Loans individually evaluated for impairment exclude TDR Loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell which totaled $584 million and $635 million at June 30, 2019 and 2018 , respectively.

Loans Held for Sale

Loans Held for Sale	6 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Loans Held for Sale	Loans Held for Sale Loans held for sale consisted of the following: June 30, 2019 December 31, 2018 (in millions) Commercial loans: Real estate, including construction $ 66 $ 27 Global banking 85 367 Total commercial 151 394 Consumer loans: Residential mortgages 40 65 Other consumer — 53 Total consumer 40 118 Total loans held for sale $ 191 $ 512 Commercial Loans Included in commercial loans held for sale are certain loans that we no longer intend to hold for investment and transferred to held for sale which totaled $23 million and $285 million at June 30, 2019 and December 31, 2018 , respectively. During both the three and six months ended June 30, 2019 , we reversed nil of the lower of amortized cost or fair value adjustment previously recorded on commercial loans held for sale as a component of other income (loss) in the consolidated statement of income as a result of an increase in fair value due to improved pricing compared with reversing less than $1 million and $3 million during the three and six months ended June 30, 2018 , respectively. Commercial loans held for sale also includes certain loans that we have elected to designate under the fair value option which consists of loans that we originate in connection with our participation in a number of syndicated credit facilities with the intent of selling them to unaffiliated third parties as well as loans that we purchase from the secondary market and hold as hedges against our exposure to certain total return swaps. The fair value of these loans totaled $128 million and $109 million at June 30, 2019 and December 31, 2018 , respectively. See Note 10, "Fair Value Option," for additional information. Consumer Loans Included in residential mortgage loans held for sale are agency-eligible residential mortgage loans which are originated and held for sale to third parties, currently on a servicing retained basis. Gains and losses from the sale of these residential mortgage loans are reflected as a component of other income (loss) in the consolidated statement of income. During the first quarter of 2019, we transferred $53 million of student loans that were previously classified as other consumer loans held for sale back to held for investment as we now intend to hold these loans for the foreseeable future. Loans held for sale are subject to market risk, liquidity risk and interest rate risk, in that their value will fluctuate as a result of changes in market conditions, as well as the credit environment. Interest rate risk for agency-eligible residential mortgage loans held for sale is partially mitigated through an economic hedging program to offset changes in the fair value of these mortgage loans held for sale, from the time of commitment to sale, attributable to changes in market interest rates. Revenue associated with this economic hedging program, which is reflected as a component of other income (loss) in the consolidated statement of income, was losses of $1 million and $2 million during the three and six months ended June 30, 2019 , respectively, compared with losses of less than $1 million during both the three and six months ended June 30, 2018 . Valuation Allowances Excluding the commercial loans designated under the fair value option discussed above, loans held for sale are recorded at the lower of amortized cost or fair value, with adjustments to fair value being recorded as a valuation allowance through other revenues. The valuation allowance on consumer loans held for sale was $2 million and $4 million at June 30, 2019 and December 31, 2018 , respectively. The valuation allowance on commercial loans held for sale was $1 million and $3 million at June 30, 2019 and December 31, 2018 , respectively.

Goodwill

Goodwill	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill Goodwill was $1,607 million at both June 30, 2019 and December 31, 2018 . Goodwill for these periods reflects accumulated impairment losses of $670 million , which were recognized in prior periods. During the first half of 2019, there were no events or changes in circumstances to indicate that it is more likely than not the fair values of any of our reporting units have reduced below their respective carrying amounts.

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Leases	Leases We have entered into operating leases for premises and equipment. As discussed more fully in Note 21, "New Accounting Pronouncements," beginning January 1, 2019, lease right-of-use ("ROU") assets and lease liabilities for operating leases are recognized at commencement date based on the present value of lease payments over the lease term, discounted using our incremental borrowing rate at the effective commencement date of each lease. Operating lease ROU assets are recorded in other assets while operating lease liabilities are recorded in interest, taxes and other liabilities. We have not entered into any finance leases. Certain leases contain options to renew or terminate the lease which are recognized as part of our ROU assets and liabilities when it is reasonably certain the options will be exercised. Certain leases also contain escalation clauses. We have lease agreements that contain both lease and non-lease components, such as maintenance costs, which are accounted for separately. Operating lease cost for fixed lease payments is recognized on a straight-line basis over the lease term. Variable lease payments for real estate taxes, insurance, maintenance and utilities, which are generally based on our pro rata share of the total property, are not included in the measurement of the ROU assets or lease liabilities and are expensed as incurred. In addition, we do not recognize ROU assets or lease liabilities for short-term leases with a term of 12 months or less, which are also expensed as incurred. We have entered into agreements to sublease certain office space, including agreements to receive rental income from our affiliates for rent. As owner or lessee of the properties, we have entered into agreements with affiliates to charge them rent based on the office space utilized by their employees during the period. See Note 14, "Related Party Transactions," for further disclosure. The following table summarizes the components of total operating lease costs, net and provides supplemental cash flow information related to leases: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (in millions) Operating lease cost $ 34 $ 66 Variable lease cost 17 31 Short-term lease cost 2 6 Sublease income (14 ) (28 ) Total operating lease costs, net $ 39 $ 75 Supplemental disclosure of cash flow information: Cash paid for amounts included in the measurement of operating lease liabilities $ 31 $ 62 ROU assets recognized for new operating lease liabilities — 10 The following table presents information about our operating lease ROU assets and liabilities: June 30, 2019 (dollars are in millions) Operating lease ROU assets (1) $ 735 Operating lease liabilities 786 Weighted-average remaining lease term 7.3 years Weighted-average discount rate 3.2 % (1) Reported net of level lease adjustments and exit cost obligations. The following table presents a maturity analysis of our operating lease liabilities at June 30, 2019 : Year Ending December 31, (in millions) 2019 $ 56 2020 135 2021 135 2022 131 2023 130 Thereafter 312 Total future operating lease payments 899 Less - imputed interest (113 ) Total operating lease liabilities $ 786 At June 30, 2019 , we had $24 million of additional operating leases for premises that have not yet commenced and are not reflected in the table above. For comparative periods prior to the adoption of the new accounting guidance on January 1, 2019, we have retained the following disclosures as previously reported. Net rental expense under operating leases, which did not include certain variable lease costs, was $24 million and $47 million during the three and six months ended June 30, 2018 , respectively. Future net minimum lease commitments under noncancellable operating lease arrangements at December 31, 2018, which did not include renewals, were as follows: Year Ending December 31, Minimum Lease Payments Minimum Sublease Income Net (in millions) 2019 $ 136 $ (58 ) $ 78 2020 125 (2 ) 123 2021 115 (1 ) 114 2022 103 — 103 2023 91 — 91 Thereafter 182 (1 ) 181 Net minimum lease commitments $ 752 $ (62 ) $ 690

Derivative Financial Instrument

Derivative Financial Instruments	6 Months Ended
	Jun. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments In the normal course of business, the derivative instruments we enter into are for trading, market making and risk management purposes. For financial reporting purposes, derivative instruments are designated in one of the following categories: (a) hedging instruments designated as qualifying hedges under derivative and hedge accounting principles, (b) financial instruments held for trading or (c) non-qualifying economic hedges. The derivative instruments held are predominantly swaps, futures, options and forward contracts. All derivatives are stated at fair value. Where we enter into enforceable master netting agreements with counterparties, the master netting agreements permit us to net those derivative asset and liability positions and to offset cash collateral held and posted with the same counterparty. The following table presents the fair value of derivative contracts by major product type on a gross basis. Gross fair values exclude the effects of both counterparty netting as well as collateral, and therefore are not representative of our exposure. The table below also presents the amounts of counterparty netting and cash collateral that have been offset in the consolidated balance sheet, as well as cash and securities collateral posted and received under enforceable master netting agreements that do not meet the criteria for netting. Derivative assets and liabilities which are not subject to an enforceable master netting agreement, or are subject to a netting agreement where an appropriate legal opinion to determine such agreements are enforceable has not been either sought or obtained, have not been netted in the following table. Where we have received or posted collateral under netting agreements where an appropriate legal opinion to determine such agreements are enforceable has not been either sought or obtained, the related collateral also has not been netted in the following table. June 30, 2019 December 31, 2018 Derivative Assets Derivative Liabilities Derivative Assets Derivative Liabilities (in millions) Derivatives accounted for as fair value hedges (1) OTC-cleared (2) $ — $ — $ 6 $ — Bilateral OTC (2) — 161 — 117 Interest rate contracts — 161 6 117 Derivatives accounted for as cash flow hedges (1) Foreign exchange contracts - bilateral OTC (2) 8 23 11 32 Interest rate contracts - bilateral OTC (2) — 31 — 13 Total derivatives accounted for as hedges 8 215 17 162 Trading derivatives not accounted for as hedges (3) Exchange-traded (2) 98 23 2 45 OTC-cleared (2) 51 18 50 14 Bilateral OTC (2) 11,204 12,504 9,866 10,780 Interest rate contracts 11,353 12,545 9,918 10,839 Exchange-traded (2) 1 28 — 15 Bilateral OTC (2) 13,360 12,993 15,897 15,684 Foreign exchange contracts 13,361 13,021 15,897 15,699 Exchange-traded (2) 16 — — — Bilateral OTC (2) 2,738 2,744 2,034 2,061 Equity contracts 2,754 2,744 2,034 2,061 Exchange-traded (2) 106 136 16 274 Bilateral OTC (2) 1,254 1,255 829 626 Precious metals contracts 1,360 1,391 845 900 OTC-cleared (2) 191 178 125 107 Bilateral OTC (2) 927 1,069 825 831 Credit contracts 1,118 1,247 950 938 Other non-qualifying derivatives not accounted for as hedges (1) Interest rate contracts - bilateral OTC (2) 207 67 133 216 Foreign exchange contracts - bilateral OTC (2) 1 8 13 2 Equity contracts - bilateral OTC (2) 1,022 157 512 805 Credit contracts - bilateral OTC (2) 1 28 6 9 Other contracts - bilateral OTC (2)(4) 5 40 5 40 Total derivatives 31,190 31,463 30,330 31,671 Less: Gross amounts of receivable / payable subject to enforceable master netting agreements (5)(7) 24,555 24,555 25,172 25,172 Less: Gross amounts of cash collateral received / posted subject to enforceable master netting agreements (6)(7) 3,439 3,627 2,020 3,675 Net amounts of derivative assets / liabilities presented in the balance sheet 3,196 3,281 3,138 2,824 Less: Gross amounts of financial instrument collateral received / posted subject to enforceable master netting agreements but not offset in the consolidated balance sheet 789 1,572 832 568 Net amounts of derivative assets / liabilities $ 2,407 $ 1,709 $ 2,306 $ 2,256 (1) Derivative assets / liabilities related to cash flow hedges, fair value hedges and derivative instruments held for purposes other than for trading are recorded in other assets / interest, taxes and other liabilities on the consolidated balance sheet. (2) Over-the-counter ("OTC") derivatives include derivatives executed and settled bilaterally with counterparties without the use of an organized exchange or central clearing house. The credit risk associated with bilateral OTC derivatives is managed through obtaining collateral and enforceable master netting agreements. OTC-cleared derivatives are executed bilaterally in the OTC market but then novated to a central clearing counterparty, whereby the central clearing counterparty becomes the counterparty to each of the original counterparties. Exchange traded derivatives are executed directly on an organized exchange. Credit risk is minimized for OTC-cleared derivatives and exchange traded derivatives through daily margining requirements. In addition, OTC-cleared interest-rate derivatives with certain central clearing counterparties are settled daily. (3) Trading related derivative assets / liabilities are recorded in trading assets / trading liabilities on the consolidated balance sheet. (4) Consists of swap agreements entered into in conjunction with the sales of Visa Inc. ("Visa") Class B common shares ("Class B Shares"). (5) Represents the netting of derivative receivable and payable balances for the same counterparty under enforceable netting agreements. (6) Represents the netting of cash collateral posted and received by counterparty under enforceable netting agreements. (7) Netting is performed at a counterparty level in cases where enforceable master netting agreements are in place, regardless of the type of derivative instrument. Therefore, we have not allocated netting to the different types of derivative instruments shown in the table above. See Note 18, "Guarantee Arrangements, Pledged Assets and Repurchase Agreements," for further information on offsetting related to resale and repurchase agreements and securities borrowing and lending arrangements. Derivatives Held for Risk Management Purposes Our risk management policy requires us to identify, analyze and manage risks arising from the activities conducted during the normal course of business. We use derivative instruments as an asset and liability management tool to manage our exposures in interest rate, foreign currency and credit risks in existing assets and liabilities, commitments and forecasted transactions. The accounting for changes in fair value of a derivative instrument will depend on whether the derivative has been designated and qualifies for hedge accounting. We designate derivative instruments to offset the fair value risk and cash flow risk arising from fixed-rate and floating-rate assets and liabilities as well as forecasted transactions. We assess the hedging relationships, both at the inception of the hedge and on an ongoing basis, using a regression approach to determine whether the designated hedging instrument is highly effective in offsetting changes in the fair value or the cash flows attributable to the hedged risk. Accounting principles for qualifying hedges require us to prepare detailed documentation describing the relationship between the hedging instrument and the hedged item, including, but not limited to, the risk management objective, the hedging strategy and the methods to assess and measure the ineffectiveness of the hedging relationship. We discontinue hedge accounting when we determine that the hedge is no longer highly effective, the hedging instrument is terminated, sold or expired, the designated forecasted transaction is not probable of occurring, or when the designation is removed by us. Fair Value Hedges In the normal course of business, we hold fixed-rate loans and securities and issue fixed-rate senior and subordinated debt obligations. The fair value of fixed-rate assets and liabilities fluctuates in response to changes in interest rates. We utilize interest rate swaps, forward and futures contracts to minimize our exposure to changes in fair value caused by interest rate volatility. The changes in the fair value of the hedged item designated in a qualifying hedge are captured as an adjustment to the carrying amount of the hedged item (basis adjustment). If the hedging relationship is discontinued and the hedged item continues to exist, the basis adjustment is amortized over the remaining life of the hedged item. The following table presents the carrying amount of hedged items in fair value hedges recognized in the consolidated balance sheet at June 30, 2019 , along with the cumulative amount of fair value hedging adjustments included in the carrying amount of those hedged items: Carrying Amount of Hedged Items (1) Cumulative Amount of Fair Value Hedging Adjustments Increasing (Decreasing) the Carrying Amount of Hedged Items Active Discontinued Total (in millions) At June 30, 2019 Securities available-for-sale ("AFS") $ 11,745 $ 716 $ 252 $ 968 Long-term debt 11,964 294 (52 ) 242 (1) The carrying amount of securities AFS represents the amortized cost basis. The following table presents information on gains and losses on derivative instruments designated and qualifying as hedging instruments and the hedged items in fair value hedges and their locations on the consolidated statement of income: Gain (Loss) on Derivatives (1) Gain (Loss) on Hedged Items (1) Net Ineffective Gain (Loss) Recognized (1) Net Interest Income Other Income (Loss) Net Interest Income Other Income (Loss) Other Income (Loss) (in millions) Three Months Ended June 30, 2019 Interest rate contracts / Securities AFS $ (404 ) $ — $ 488 $ — $ — Interest rate contracts / Long-term debt 153 — (290 ) — — Total $ (251 ) $ — $ 198 $ — $ — Three Months Ended June 30, 2018 Interest rate contracts / Securities AFS $ (10 ) $ 125 $ 89 $ (117 ) $ 8 Interest rate contracts / Long-term debt (14 ) (7 ) (53 ) 4 (3 ) Total $ (24 ) $ 118 $ 36 $ (113 ) $ 5 Six Months Ended June 30, 2019 Interest rate contracts / Securities AFS $ (661 ) $ — $ 838 $ — $ — Interest rate contracts / Long-term debt 237 — (489 ) — — Total $ (424 ) $ — $ 349 $ — $ — Six Months Ended June 30, 2018 Interest rate contracts / Securities AFS $ (33 ) $ 487 $ 176 $ (474 ) $ 13 Interest rate contracts / Long-term debt (20 ) (67 ) (110 ) 65 (2 ) Total $ (53 ) $ 420 $ 66 $ (409 ) $ 11 (1) As a result of adopting new accounting guidance discussed in Note 21, "New Accounting Pronouncements," beginning January 1, 2019, we report gains and losses on the derivatives and the hedged items in fair value hedges in net interest income. Prior to January 1, 2019, fair value hedge ineffectiveness was separately measured and reported in other income (loss). Cash Flow Hedges We own or issue floating rate financial instruments and enter into forecasted transactions that give rise to variability in future cash flows. As a part of our risk management strategy, we use interest rate swaps, currency swaps and futures contracts to mitigate risk associated with variability in the cash flows. Changes in fair value of a derivative instrument associated with a qualifying cash flow hedge are recognized in other comprehensive income (loss). When the cash flows being hedged materialize and are recorded in income or expense, the associated gain or loss from the hedging derivative previously recorded in accumulated other comprehensive loss ("AOCI") is reclassified into earnings in the same accounting period in which the designated forecasted transaction or hedged item affects earnings. If a cash flow hedge of a forecasted transaction is discontinued because it is no longer highly effective, or if the hedge relationship is terminated, the cumulative gain or loss on the hedging derivative to that date will continue to be reported in AOCI unless it is probable that the hedged forecasted transaction will not occur by the end of the originally specified time period as documented at the inception of the hedge, at which time the cumulative gain or loss is released into earnings. At June 30, 2019 , active cash flow hedge relationships extend or mature through July 2036 . During the three and six months ended June 30, 2019 , respectively, $9 million and $19 million of losses related to discontinued cash flow hedge relationships were amortized to earnings from AOCI compared with losses of $5 million and $9 million during the three and six months ended June 30, 2018 , respectively. During the next twelve months, we expect to amortize $31 million of remaining losses to earnings resulting from these discontinued cash flow hedges. The interest accrual related to the hedging instruments is recognized in net interest income. The following table presents information on gains and losses on derivative instruments designated and qualifying as hedging instruments in cash flow hedges (including amounts recognized in AOCI from discontinued cash flow hedges) and their locations on the consolidated statement of income: Gain (Loss) Recognized in AOCI on Derivatives (1) Location of Gain (Loss) Reclassified from AOCI into Income (1) Gain (Loss) Reclassified From AOCI into Income (1) 2019 2018 2019 2018 (in millions) Three Months Ended June 30, Foreign exchange contracts $ — $ (1 ) Net interest income $ — $ — Interest rate contracts (2 ) 9 Net interest income (9 ) (5 ) Total $ (2 ) $ 8 $ (9 ) $ (5 ) Six Months Ended June 30, Foreign exchange contracts $ 1 $ (6 ) Net interest income $ — $ — Interest rate contracts 5 12 Net interest income (19 ) (9 ) Total $ 6 $ 6 $ (19 ) $ (9 ) (1) As a result of adopting new accounting guidance discussed in Note 21, "New Accounting Pronouncements," beginning January 1, 2019, gains and losses on the derivatives in cash flow hedges are initially reported in AOCI and then reclassified into earnings in the same accounting period in which the designated forecasted transaction or hedged item affects earnings. Prior to January 1, 2019, cash flow hedge ineffectiveness was separately measured and reported immediately in other income (loss). Cash flow hedge ineffectiveness was immaterial during the three and six months ended June 30, 2018 . Trading Derivatives and Non-Qualifying Hedging Activities In addition to risk management, we also enter into derivative contracts, including buy- and sell-protection credit derivatives, for the purposes of trading and market making, or repackaging risks to form structured trades to meet clients' risk taking objectives. Additionally, we buy or sell securities and use derivatives to mitigate the market risks arising from our trading activities with our clients that exceed our risk appetite. We also use buy-protection credit derivatives to manage our counterparty credit risk exposure. Where we enter into derivatives for trading purposes, realized and unrealized gains and losses are recognized in trading revenue. Counterparty credit risk associated with OTC derivatives, including risk-mitigating buy-protection credit derivatives, are recognized as an adjustment to the fair value of the derivatives and are recorded in trading revenue. Our non-qualifying hedging and other activities include: • Derivative contracts related to the fixed-rate long-term debt issuances and hybrid instruments, including all structured notes and deposits, for which we have elected fair value option accounting. These derivative contracts are non-qualifying hedges but are considered economic hedges. • Credit default swaps which are designated as economic hedges against the credit risks within our loan portfolio. In the event of an impairment loss occurring in a loan that is economically hedged, the impairment loss is recognized as provision for credit losses while the gain on the credit default swap is recorded as other income (loss). • Swap agreements entered into in conjunction with the sales of Visa Class B Shares to a third party to retain the litigation risk associated with the Class B Shares sold until the related litigation is settled and the Class B Shares can be converted into Class A common shares ("Class A Shares"). See Note 18, "Guarantee Arrangements, Pledged Assets and Repurchase Agreements," for additional information. • Forward purchases or sales of to-be-announced ("TBA") securities used to economically hedge changes in the fair value of agency-eligible residential mortgage loans held for sale attributable to changes in market interest rates. Changes in the fair value of TBA positions, which are considered derivatives, are recorded in other income (loss). See Note 6, "Loans Held for Sale," for additional information. Derivative instruments designated as economic hedges that do not qualify for hedge accounting are recorded at fair value through profit and loss. Realized and unrealized gains and losses on economic hedges are recognized in gain (loss) on instruments designated at fair value and related derivatives or other income (loss) while the derivative asset or liability positions are reflected as other assets or other liabilities. The following table presents information on gains and losses on derivative instruments held for trading purposes and their locations on the consolidated statement of income: Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest rate contracts Trading revenue $ (171 ) $ 126 $ (115 ) $ 329 Foreign exchange contracts Trading revenue 677 28 814 (72 ) Equity contracts Trading revenue (61 ) 2 (150 ) (1 ) Precious metals contracts Trading revenue (388 ) 85 (522 ) 215 Credit contracts Trading revenue (145 ) (1 ) (267 ) (4 ) Total $ (88 ) $ 240 $ (240 ) $ 467 The following table presents information on gains and losses on derivative instruments held for non-qualifying hedging and other activities and their locations on the consolidated statement of income: Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest rate contracts Gain (loss) on instruments designated at fair value and related derivatives $ 180 $ (54 ) $ 336 $ (216 ) Interest rate contracts Other income (loss) (1 ) — (2 ) — Foreign exchange contracts Gain (loss) on instruments designated at fair value and related derivatives 1 (8 ) — (10 ) Equity contracts Gain (loss) on instruments designated at fair value and related derivatives 324 167 1,238 (172 ) Credit contracts Other income (loss) (4 ) 12 (14 ) 10 Other contracts (1) Other income (loss) (3 ) (12 ) (9 ) (14 ) Total $ 497 $ 105 $ 1,549 $ (402 ) (1) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares. Credit-Risk Related Contingent Features The majority of our derivative contracts contain provisions that require us to maintain a specific credit rating from each of the major credit rating agencies. Sometimes the derivative instrument transactions are a part of broader structured product transactions. If our credit ratings were to fall below the current ratings, the counterparties to our derivative instruments could demand us to post additional collateral. The amount of additional collateral required to be posted will depend on whether we are downgraded by one or more notches. The aggregate fair value of all derivative instruments with credit-risk related contingent features that were in a net liability position at June 30, 2019 was $622 million , for which we had posted collateral of $304 million . The aggregate fair value of all derivative instruments with credit-risk-related contingent features that were in a net liability position at December 31, 2018 was $979 million , for which we had posted collateral of $422 million . Substantially all of the collateral posted is in the form of cash or securities available-for-sale. See Note 18, "Guarantee Arrangements, Pledged Assets and Repurchase Agreements," for further details. The following table presents the amount of additional collateral that we would be required to post (from the current collateral level) related to derivative instruments with credit-risk related contingent features if our long-term ratings were downgraded by one or two notches. A downgrade by a single rating agency that does not result in a rating lower than a preexisting corresponding rating provided by another rating agency will generally not result in additional collateral. One-notch downgrade Two-notch downgrade (in millions) Amount of additional collateral to be posted upon downgrade $ 34 $ 55 Notional Value of Derivative Contracts The following table summarizes the notional values of derivative contracts: June 30, 2019 December 31, 2018 (in millions) Interest rate: Futures and forwards $ 653,615 $ 787,049 Swaps 3,062,626 3,203,048 Options written 106,238 106,009 Options purchased 110,682 107,561 3,933,161 4,203,667 Foreign exchange: Swaps, futures and forwards 1,169,693 1,052,088 Options written 54,583 30,567 Options purchased 55,027 31,069 Spot 42,539 31,084 1,321,842 1,144,808 Commodities, equities and precious metals: Swaps, futures and forwards 56,428 41,328 Options written 35,191 28,595 Options purchased 46,245 40,236 137,864 110,159 Credit derivatives 122,874 97,298 Other contracts (1) 969 736 Total $ 5,516,710 $ 5,556,668 (1) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares.

Fair Value Option

Fair Value Option	6 Months Ended
	Jun. 30, 2019
Fair Value Option [Abstract]
Fair Value Option	Fair Value Option We report our results to HSBC in accordance with HSBC Group accounting and reporting policies ("Group Reporting Basis"), which apply International Financial Reporting Standards ("IFRSs") as issued by the International Accounting Standards Board ("IASB") and endorsed by the European Union ("EU"). We typically have elected to apply fair value option ("FVO") accounting to selected financial instruments to align the measurement attributes of those instruments under U.S. GAAP and the Group Reporting Basis and to simplify the accounting model applied to those financial instruments. We elected to apply FVO accounting to certain commercial loans held for sale, certain securities purchased and sold under resale and repurchase agreements, certain fixed-rate long-term debt issuances and all of our hybrid instruments, including structured notes and deposits. Excluding the fair value movement on fair value option liabilities attributable to our own credit spread, which is recorded in other comprehensive income (loss), changes in the fair value of fair value option assets and liabilities as well as the mark-to-market adjustment on the related derivatives and the net realized gains or losses on these derivatives are reported in gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income. Loans We elected to apply FVO accounting to certain commercial syndicated loans which are originated with the intent to sell and certain commercial loans that we purchased from the secondary market and hold as hedges against our exposure to certain total return swaps and include these loans as loans held for sale in the consolidated balance sheet. The election allows us to account for these loans at fair value which is consistent with the manner in which the instruments are managed. Where available, fair value is based on observable market pricing obtained from independent sources, relevant broker quotes or observed market prices of instruments with similar characteristics. Where observable market parameters are not available, fair value is determined based on contractual cash flows adjusted for estimates of prepayment rates, expected default rates and loss severity discounted at management's estimate of the expected rate of return required by market participants. We also consider loan-specific risk mitigating factors such as collateral arrangements in determining the fair value estimate. Interest from these loans is recorded as interest income in the consolidated statement of income. Because a substantial majority of the loans elected for the fair value option are floating rate assets, changes in their fair value are primarily attributable to changes in loan-specific credit risk factors. The components of gain (loss) related to loans designated at fair value are summarized in the table below. At June 30, 2019 and December 31, 2018 , no loans for which the fair value option has been elected were 90 days or more past due or in nonaccrual status. Resale and Repurchase Agreements We elected to apply FVO accounting to certain securities purchased and sold under resale and repurchase agreements which are trading in nature. The election allows us to account for these resale and repurchase agreements at fair value which is consistent with the manner in which the instruments are managed. The fair value of the resale and repurchase agreements is determined using market rates currently offered on comparable transactions with similar underlying collateral and maturities. Interest on these resale and repurchase agreements is recorded as interest income or expense in the consolidated statement of income. The components of gain (loss) related to these resale and repurchase agreements designated at fair value are summarized in the table below. Long-Term Debt (Own Debt Issuances) We elected to apply FVO accounting for certain fixed-rate long-term debt for which we had applied or otherwise would elect to apply fair value hedge accounting. The election allows us to achieve a similar accounting effect without having to meet the hedge accounting requirements. The own debt issuances elected under FVO are traded in secondary markets and, as such, the fair value is determined based on observed prices for the specific instruments. The observed market price of these instruments reflects the effect of changes to our own credit spreads and interest rates. Interest on the fixed-rate debt accounted for under FVO is recorded as interest expense in the consolidated statement of income. The components of gain (loss) in the consolidated statement of income related to long-term debt designated at fair value are summarized in the table below. Hybrid Instruments We elected to apply FVO accounting to all of our hybrid instruments issued, including structured notes and deposits. The valuation of the hybrid instruments is predominantly driven by the derivative features embedded within the instruments and our own credit risk. Cash flows of the hybrid instruments in their entirety, including the embedded derivatives, are discounted at an appropriate rate for the applicable duration of the instrument adjusted for our own credit spreads. The credit spreads applied to structured notes are determined with reference to our own debt issuance rates observed in the primary and secondary markets, internal funding rates, and structured note rates in recent executions while the credit spreads applied to structured deposits are determined using market rates currently offered on comparable deposits with similar characteristics and maturities. Interest on this debt is recorded as interest expense in the consolidated statement of income. The components of gain (loss) in the consolidated statement of income related to hybrid instruments designated at fair value are summarized in the table below. The following table summarizes the fair value and unpaid principal balance for items we account for under FVO: Fair Value Unpaid Principal Balance Fair Value Over (Under) Unpaid Principal Balance (in millions) At June 30, 2019 Commercial loans held for sale $ 128 $ 136 $ (8 ) Securities sold under repurchase agreements 222 222 — Fixed rate long-term debt 2,160 1,750 410 Hybrid instruments: Structured deposits 8,455 8,472 (17 ) Structured notes 9,819 8,998 821 At December 31, 2018 Commercial loans held for sale $ 109 $ 120 $ (11 ) Securities sold under repurchase agreements 560 560 — Fixed rate long-term debt 1,935 1,750 185 Hybrid instruments: Structured deposits 8,154 8,441 (287 ) Structured notes 9,314 9,546 (232 ) Components of Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives The following table summarizes the components of gain (loss) on instruments designated at fair value and related derivatives reflected in the consolidated statement of income for the three and six months ended June 30, 2019 and 2018 : Loans Securities Sold Under Repurchase Agreements Long-Term Debt Hybrid Instruments Total (in millions) Three Months Ended June 30, 2019 Interest rate and other components (1) $ — $ — $ (100 ) $ (422 ) $ (522 ) Credit risk component (2) — — — — — Total mark-to-market on financial instruments designated at fair value — — (100 ) (422 ) (522 ) Mark-to-market on related derivatives — — 83 413 496 Net realized gain on related long-term debt derivatives — — 9 — 9 Gain (loss) on instruments designated at fair value and related derivatives $ — $ — $ (8 ) $ (9 ) $ (17 ) Three Months Ended June 30, 2018 Interest rate and other components (1) $ — $ 1 $ 34 $ (135 ) $ (100 ) Credit risk component (2) (1 ) — — — (1 ) Total mark-to-market on financial instruments designated at fair value (1 ) 1 34 (135 ) (101 ) Mark-to-market on related derivatives — — (33 ) 127 94 Net realized gain on related long-term debt derivatives — — 11 — 11 Gain (loss) on instruments designated at fair value and related derivatives $ (1 ) $ 1 $ 12 $ (8 ) $ 4 Six Months Ended June 30, 2019 Interest rate and other components (1) $ — $ — $ (169 ) $ (1,434 ) $ (1,603 ) Credit risk component (2) 3 — — — 3 Total mark-to-market on financial instruments designated at fair value 3 — (169 ) (1,434 ) (1,600 ) Mark-to-market on related derivatives — — 136 1,419 1,555 Net realized gain on related long-term debt derivatives — — 19 — 19 Gain (loss) on instruments designated at fair value and related derivatives $ 3 $ — $ (14 ) $ (15 ) $ (26 ) Six Months Ended June 30, 2018 Interest rate and other components (1) $ — $ — $ 122 $ 307 $ 429 Credit risk component (2) 3 — — — 3 Total mark-to-market on financial instruments designated at fair value 3 — 122 307 432 Mark-to-market on related derivatives — — (110 ) (312 ) (422 ) Net realized gain on related long-term debt derivatives — — 24 — 24 Gain (loss) on instruments designated at fair value and related derivatives $ 3 $ — $ 36 $ (5 ) $ 34 (1) As it relates to hybrid instruments, interest rate and other components primarily includes interest rate, foreign exchange and equity contract risks. (2) The fair value movement on fair value option liabilities attributable to our own credit spread is recorded in other comprehensive income (loss).

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Accumulated other comprehensive loss includes certain items that are reported directly within a separate component of equity. The following table presents changes in accumulated other comprehensive loss balances: Three Months Ended June 30, 2019 2018 (in millions) Unrealized gains (losses) on investment securities: Balance at beginning of period $ (340 ) $ (494 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $73 million and $(22) million, respectively 235 (73 ) Reclassification adjustment for gains realized in net income, net of tax of $(5) and $(3) million, respectively (1) (18 ) (7 ) Amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity realized in net income, net of tax of $1 million and $1 million, respectively (2) 3 4 Total other comprehensive income (loss) for period 220 (76 ) Balance at end of period (120 ) (570 ) Unrealized gains (losses) on fair value option liabilities attributable to our own credit spread: Balance at beginning of period 190 (11 ) Other comprehensive income (loss) for period: Net unrealized gains arising during the period, net of tax of $2 million and $41 million, respectively 7 129 Total other comprehensive income for period 7 129 Balance at end of period 197 118 Unrealized gains (losses) on derivatives designated as cash flow hedges: Balance at beginning of period (145 ) (197 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $(1) million and $2 million, respectively (1 ) 6 Reclassification adjustment for losses realized in net income, net of tax of $3 million and $1 million, respectively (3) 6 4 Total other comprehensive income for period 5 10 Balance at end of period (140 ) (187 ) Pension and postretirement benefit liability: Balance at beginning of period 8 4 Other comprehensive income (loss) for period: Change in unfunded pension and postretirement liability, net of tax of nil and less than $1 million, respectively — (1 ) Total other comprehensive loss for period — (1 ) Balance at end of period 8 3 Total accumulated other comprehensive loss at end of period $ (55 ) $ (636 ) Six Months Ended June 30, 2019 2018 (in millions) Unrealized gains (losses) on investment securities: Balance at beginning of period $ (519 ) $ (250 ) Cumulative effect adjustment to initially apply new accounting guidance for equity investments which were previously classified as available-for-sale, net of tax of $2 million (4) — 4 Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — (53 ) Balance at beginning of period, adjusted (519 ) (299 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $128 million and $(85) million, respectively 415 (266 ) Reclassification adjustment for gains realized in net income, net of tax of $(7) million and $(4) million, respectively (1) (23 ) (11 ) Amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity realized in net income, net of tax of $2 million and $2 million, respectively (2) 7 6 Total other comprehensive income (loss) for period 399 (271 ) Balance at end of period (120 ) (570 ) Unrealized gains (losses) on fair value option liabilities attributable to our own credit spread: Balance at beginning of period 301 (19 ) Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — (4 ) Balance at beginning of period, adjusted 301 (23 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $(33) million and $46 million, respectively (104 ) 141 Total other comprehensive income (loss) for period (104 ) 141 Balance at end of period 197 118 Unrealized gains (losses) on derivatives designated as cash flow hedges: Balance at beginning of period (159 ) (164 ) Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — (35 ) Balance at beginning of period, adjusted (159 ) (199 ) Other comprehensive income (loss) for period: Net unrealized gains arising during period, net of tax of $1 million and $2 million, respectively 5 5 Reclassification adjustment for losses realized in net income, net of tax of $5 million and $2 million, respectively (3) 14 7 Total other comprehensive income for period 19 12 Balance at end of period (140 ) (187 ) Pension and postretirement benefit liability: Balance at beginning of period 11 2 Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — 1 Balance at beginning of period, adjusted 11 3 Other comprehensive income (loss) for period: Change in unfunded pension and postretirement liability, net of tax of $(1) million and less than $1 million, respectively (3 ) — Total other comprehensive loss for period (3 ) — Balance at end of period 8 3 Total accumulated other comprehensive loss at end of period $ (55 ) $ (636 ) (1) Amount reclassified to net income is included in other securities gains, net in our consolidated statement of income. (2) Amount amortized to net income is included in interest income in our consolidated statement of income. During 2014, we transferred securities from available-for-sale to held-to-maturity. At the date of transfer, AOCI included net pretax unrealized losses related to the transferred securities which are being amortized over the remaining contractual life of each security as an adjustment of yield in a manner consistent with the amortization of any premium or discount. (3) Amount reclassified to net income is included in net interest income in our consolidated statement of income. (4) See Note 2, "Summary of Significant Accounting Polices and New Accounting Pronouncements," in our 2018 Form 10-K for additional discussion.

Pension and Other Postretiremen

Pension and Other Postretirement Benefits	6 Months Ended
	Jun. 30, 2019
Retirement Benefits [Abstract]
Pension and Other Postretirement Benefits	Pension and Other Postretirement Benefits Defined Benefit Pension Plan The table below reflects the portion of pension expense and its related components of the combined HSBC North America Pension Plan (either the "HSBC North America Pension Plan" or the "Plan") which has been allocated to us and is recorded in our consolidated statement of income. We have not been allocated any portion of the Plan's net pension liability. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest cost on projected benefit obligation $ 14 $ 15 $ 29 $ 30 Expected return on plan assets (19 ) (19 ) (37 ) (40 ) Amortization of net actuarial loss 5 5 12 10 Administrative costs 1 1 2 2 Pension expense $ 1 $ 2 $ 6 $ 2 Postretirement Plans Other Than Pensions Our employees also participate in plans which provide medical and life insurance benefits to certain retirees and eligible dependents. These plans cover substantially all employees who meet certain age and vested service requirements. We have instituted dollar limits on payments under the plans to control the cost of future medical benefits. The following table reflects the components of the net periodic postretirement benefit cost: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest cost on accumulated benefit obligation $ 1 $ 1 $ 1 $ 1 Amortization of net actuarial gain (1 ) — (1 ) — Net periodic postretirement benefit cost $ — $ 1 $ — $ 1

Fee Income from Contracts with

Fee Income from Contracts with Customers	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Fee Income from Contracts with Customers	Fee Income from Contracts with Customers The following table summarizes fee income from contracts with customers disaggregated by type of activity, as well as a reconciliation to total other revenues, during the three and six months ended June 30, 2019 and 2018 . See Note 21, "Fee Income from Contracts with Customers," in our 2018 Form 10-K for a description of the various types of fee-based activities and how revenue associated with these activities is recognized. There have been no significant changes in these activities since December 31, 2018 . Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Credit card fees, net $ 18 $ 15 $ 30 $ 26 Trust and investment management fees 31 34 61 72 Other fees and commissions: Account services (1) 68 79 133 148 Credit facilities 81 86 150 164 Other fees (1) 13 19 26 32 Total other fees and commissions 162 184 309 344 Servicing and other fees from HSBC affiliates 88 87 169 186 Insurance (2) 4 3 6 6 Total fee income from contracts with customers 303 323 575 634 Other non-fee revenues 133 214 251 416 Total other revenues (3) $ 436 $ 537 $ 826 $ 1,050 (1) During the fourth quarter of 2018, we concluded that certain wire transfer fees would be better presented in account services as opposed to other fees. As a result, we have reclassified $6 million and $ 10 million of wire transfer fees from other fees to account services during the three and six months ended June 30, 2018 to conform with the current year presentation. (2) Included within other income (loss) in the consolidated statement of income. (3) See Note 15, "Business Segments," for a reconciliation of total other revenues on a U.S. GAAP basis to other operating income for each business segment under the Group Reporting Basis. Credit card fees, net We recognized interchange fees of $26 million and $48 million during the three and six months ended June 30, 2019 , respectively, compared with $22 million and $43 million during the three and six months ended June 30, 2018 , respectively. Credit card rewards program costs totaled $10 million and $22 million during the three and six months ended June 30, 2019 , respectively, compared with $9 million and $21 million during the three and six months ended June 30, 2018 , respectively. Deferred Fee Income Information related to deferred fee income on loan commitments, revolving credit facilities and standby letters of credit is included in Note 18, "Guarantee Arrangements, Pledged Assets and Repurchase Agreements," and Note 19, "Fair Value Measurements." Excluding these items, we had deferred fee income related to certain account service fees that are paid upfront and recognized over the service period and annual fees on credit cards which collectively totaled $2 million at both June 30, 2019 and December 31, 2018 . We expect to recognize this revenue over a remaining period of one year or less. Other than as described above under trust and investment management fees, we do not use significant judgments in the determination of the amount and timing of fee income from contracts with customers. Additionally, costs to obtain or fulfill contracts with customers were immaterial.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions In the normal course of business, we conduct transactions with HSBC and its subsidiaries. HSBC policy requires that these transactions occur at prevailing market rates and terms and, where applicable, these transactions are compliant with United States banking regulations. All extensions of credit by (and certain credit exposures of) HSBC Bank USA, National Association ("HSBC Bank USA") to other HSBC affiliates (other than Federal Deposit Insurance Corporation insured banks) are legally required to be secured by eligible collateral. The following tables and discussions below present the more significant related party balances and the income (expense) generated by related party transactions: June 30, 2019 December 31, 2018 (in millions) Assets: Cash and due from banks $ 250 $ 245 Interest bearing deposits with banks 790 1,000 Trading assets 298 102 Loans 3,096 2,274 Other (1) 289 169 Total assets $ 4,723 $ 3,790 Liabilities: Deposits $ 13,301 $ 12,000 Trading liabilities 157 349 Short-term borrowings 1,518 638 Long-term debt 7,847 7,845 Other (1) 392 333 Total liabilities $ 23,215 $ 21,165 (1) Other assets and other liabilities primarily consist of derivative balances associated with hedging activities and other miscellaneous account receivables and payables. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Income (Expense): Interest income $ 47 $ 24 $ 90 $ 46 Interest expense (152 ) (90 ) (276 ) (168 ) Net interest expense (105 ) (66 ) (186 ) (122 ) Trading revenue (expense) (9 ) (627 ) (1,523 ) 531 Servicing and other fees from HSBC affiliates: HSBC Bank plc 46 43 81 84 HSBC Markets (USA) Inc. ("HMUS") 27 30 57 61 Other HSBC affiliates 15 14 31 41 Total servicing and other fees from HSBC affiliates 88 87 169 186 Gain (loss) on instruments designated at fair value and related derivatives 412 135 1,420 (303 ) Support services from HSBC affiliates: HSBC Technology & Services (USA) ("HTSU") (298 ) (310 ) (575 ) (608 ) HMUS (23 ) (25 ) (50 ) (56 ) Other HSBC affiliates (90 ) (70 ) (166 ) (152 ) Total support services from HSBC affiliates (411 ) (405 ) (791 ) (816 ) Rental income from HSBC affiliates, net (1) 12 14 24 26 Stock based compensation expense (2) (8 ) (10 ) (14 ) (15 ) (1) We receive rental income from our affiliates, and in some cases pay rental expense to our affiliates, for rent on certain office space. Net rental income from our affiliates is recorded as a component of occupancy expense, net in our consolidated statement of income. (2) Employees may participate in one or more stock compensation plans sponsored by HSBC. These expenses are included in salaries and employee benefits in our consolidated statement of income. Certain employees are also eligible to participate in a defined benefit pension plan and other postretirement plans sponsored by HSBC North America which are discussed in Note 12, "Pension and Other Postretirement Benefits." Funding Arrangements with HSBC Affiliates: We use HSBC affiliates to fund a portion of our borrowing and liquidity needs. At both June 30, 2019 and December 31, 2018 , long-term debt with affiliates reflected $7.8 billion of borrowings from HSBC North America. The outstanding balances include $1.5 billion of fixed-rate senior debt which matures in March 2021, $2.0 billion of fixed-rate senior debt which matures in May 2021, $0.8 billion of floating-rate subordinated debt which matures in May 2025, $2.0 billion of fixed-rate senior debt which matures in September 2025 and $1.5 billion of fixed-rate senior debt which matures in March 2026. We have a $150 million uncommitted line of credit with HSBC North America. There was no outstanding balance under this credit facility at either June 30, 2019 or December 31, 2018 . We have also incurred short-term borrowings with certain affiliates, largely securities sold under repurchase agreements with HSBC Securities (USA) Inc. ("HSI"). In addition, certain affiliates have also placed deposits with us. Lending and Derivative Related Arrangements Extended to HSBC Affiliates: At June 30, 2019 and December 31, 2018 , we had the following loan balances outstanding with HSBC affiliates: June 30, 2019 December 31, 2018 (in millions) HMUS and subsidiaries $ 2,835 $ 2,235 HSBC Bank Canada 250 — Other short-term affiliate lending 11 39 Total loans $ 3,096 $ 2,274 HMUS and subsidiaries We have extended loans and lines, some of them uncommitted, to HMUS and its subsidiaries in the amount of $12.8 billion at both June 30, 2019 and December 31, 2018 of which $2.8 billion and $2.2 billion , respectively, was outstanding. The maturities of the outstanding balances range from overnight to three months. Each borrowing is re-evaluated prior to its maturity date and either extended or allowed to mature. HSBC Bank Canada We have extended an uncommitted line of credit to HSBC Bank Canada in the amount of $500 million at both June 30, 2019 and December 31, 2018 of which $250 million and nil was outstanding at June 30, 2019 and December 31, 2018 , respectively. The outstanding balance matures in the third quarter of 2019. We have extended lines of credit to various other HSBC affiliates totaling $4.2 billion which did not have any outstanding balances at either June 30, 2019 or December 31, 2018 . Other short-term affiliate lending In addition to loans and lines extended to affiliates discussed above, from time to time we may extend loans to affiliates which are generally short term in nature. At June 30, 2019 and December 31, 2018 , there were $11 million and $39 million , respectively, of these loans outstanding. Derivative contracts As part of a global HSBC strategy to offset interest rate or other market risks associated with certain securities, debt issues and derivative contracts with unaffiliated third parties, we routinely enter into derivative transactions with HSBC Bank plc and other HSBC affiliates. The notional value of derivative contracts related to these transactions was approximately $935.3 billion and $809.5 billion at June 30, 2019 and December 31, 2018 , respectively. The net credit exposure (defined as the net fair value of derivative assets and liabilities, including any collateral received) related to the contracts was approximately $337 million and $108 million at June 30, 2019 and December 31, 2018 , respectively. Our Global Banking and Markets business accounts for these transactions on a mark to market basis, with the change in value of contracts with HSBC affiliates substantially offset by the change in value of related contracts entered into with unaffiliated third parties. Services Provided Between HSBC Affiliates: Under multiple service level agreements, we provide services to and receive services from various HSBC affiliates. These activities are summarized in Note 22, "Related Party Transactions," in our 2018 Form 10-K. There have been no significant changes in these activities since December 31, 2018 . Other Transactions with HSBC Affiliates: At both June 30, 2019 and December 31, 2018 , we had $1,265 million of non-cumulative preferred stock issued and outstanding to HSBC North America. See Note 17, "Preferred Stock," in our 2018 Form 10-K for additional details. During the first quarter of 2019, we paid a distribution on our common stock of $2.4 billion from surplus capital to HSBC North America. See Note 16, "Retained Earnings and Regulatory Capital Requirements," for additional details.

Business Segments

Business Segments	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Business Segments	Business Segments We have five distinct business segments that we utilize for management reporting and analysis purposes, which are aligned with HSBC's global business strategy: Retail Banking and Wealth Management ("RBWM"), Commercial Banking ("CMB"), Global Banking and Markets ("GB&M"), Private Banking ("PB") and a Corporate Center ("CC"). There have been no changes in the basis of our segmentation as compared with the presentation in our 2018 Form 10-K. Net interest income of each segment represents the difference between actual interest earned on assets and interest incurred on liabilities of the segment, adjusted for a funding charge or credit that includes both interest rate and liquidity components. Segments are charged a cost to fund assets (e.g. customer loans) and receive a funding credit for funds provided (e.g. customer deposits) based on equivalent market rates that incorporate both repricing (interest rate risk) and tenor (liquidity) characteristics. The objective of these charges/credits is to transfer interest rate risk from the segments to one centralized unit in Balance Sheet Management, recognize term funding costs/benefits and more appropriately reflect the profitability of the segments. Certain other revenue and operating expense amounts are also apportioned among the business segments based upon the benefits derived from this activity or the relationship of this activity to other segment activity. These inter-segment transactions have not been eliminated, and we generally account for them as if they were with third parties. Our segment results are presented in accordance with HSBC Group accounting and reporting policies, which apply IFRSs as issued by the IASB and endorsed by the EU, and, as a result, our segment results are prepared and presented using financial information prepared on the Group Reporting Basis as operating results are monitored and reviewed, trends are evaluated and decisions about allocating resources, such as employees, are primarily made on this basis. We continue, however, to monitor capital adequacy and report to regulatory agencies on a U.S. GAAP basis. There have been no changes in the measurement of segment profit as compared with the presentation in our 2018 Form 10-K. A summary of significant differences between U.S. GAAP and the Group Reporting Basis as they impact our results are summarized in Note 23, "Business Segments," in our 2018 Form 10-K. Other than the changes discussed below, there have been no other significant changes since December 31, 2018 in the differences between U.S. GAAP and the Group Reporting Basis impacting our results. Leases - In January 2019, new accounting guidance was adopted for leases under both U.S. GAAP and the Group Reporting Basis. Under U.S. GAAP, expense on operating leases is generally recognized on a straight-line basis. Under the Group Reporting Basis, all leases are recognized as financing arrangements with interest expense on the lease obligation and depreciation of the ROU asset recorded over the remaining life of the lease. Property - The sale and leaseback of our 452 Fifth Avenue property, including the 1 W. 39th Street building, in 2010 resulted in the recognition of a gain under the Group Reporting Basis, while under U.S. GAAP, such gain was historically deferred and was being recognized over the lease term. As a result of adopting the new accounting guidance for leases under U.S. GAAP as discussed above, we recorded a cumulative effect adjustment to recognize the previously deferred gain in retained earnings as of January 1, 2019. The following table summarizes the results for each segment on a Group Reporting Basis, as well as provides a reconciliation of total results under the Group Reporting Basis to U.S. GAAP consolidated totals: Group Reporting Basis Consolidated Amounts RBWM CMB GB&M PB CC Total Group Reporting Basis Adjustments (1) Group Reporting Basis Reclassi- fications (2) U.S. GAAP Consolidated Totals (in millions) Three Months Ended June 30, 2019 Net interest income $ 217 $ 202 $ 136 $ 37 $ 18 $ 610 $ 3 $ (73 ) $ 540 Other operating income 74 55 170 17 49 365 (3 ) 74 436 Total operating income 291 257 306 54 67 975 — 1 976 Expected credit losses / provision for credit losses 12 9 2 2 — 25 23 (2 ) 46 279 248 304 52 67 950 (23 ) 3 930 Operating expenses 305 142 210 56 48 761 10 3 774 Profit (loss) before income tax expense $ (26 ) $ 106 $ 94 $ (4 ) $ 19 $ 189 $ (33 ) $ — $ 156 Three Months Ended June 30, 2018 Net interest income $ 225 $ 195 $ 151 $ 43 $ 18 $ 632 $ 6 $ (83 ) $ 555 Other operating income 71 58 252 16 72 469 (9 ) 77 537 Total operating income 296 253 403 59 90 1,101 (3 ) (6 ) 1,092 Expected credit losses / provision for credit losses 3 (36 ) (143 ) — 1 (175 ) 118 12 (45 ) 293 289 546 59 89 1,276 (121 ) (18 ) 1,137 Operating expenses 341 139 209 61 54 804 — (18 ) 786 Profit (loss) before income tax expense $ (48 ) $ 150 $ 337 $ (2 ) $ 35 $ 472 $ (121 ) $ — $ 351 Six Months Ended June 30, 2019 Net interest income $ 438 $ 403 $ 287 $ 74 $ 32 $ 1,234 $ 9 $ (141 ) $ 1,102 Other operating income 139 113 345 33 73 703 (20 ) 143 826 Total operating income 577 516 632 107 105 1,937 (11 ) 2 1,928 Expected credit losses / provision for credit losses 33 15 (15 ) 1 1 35 64 5 104 544 501 647 106 104 1,902 (75 ) (3 ) 1,824 Operating expenses 616 280 416 109 88 1,509 18 (3 ) 1,524 Profit (loss) before income tax expense $ (72 ) $ 221 $ 231 $ (3 ) $ 16 $ 393 $ (93 ) $ — $ 300 Balances at end of period: Total assets $ 18,907 $ 26,735 $ 87,114 $ 6,952 $ 76,055 $ 215,763 $ (31,700 ) $ — $ 184,063 Total loans, net 17,031 25,513 19,599 5,863 2,322 70,328 (2,340 ) 3,877 71,865 Goodwill 581 358 — 321 — 1,260 347 — 1,607 Total deposits 33,606 23,554 29,674 7,226 6,021 100,081 (3,434 ) 20,314 116,961 Group Reporting Basis Consolidated Amounts RBWM CMB GB&M PB CC Total Group Reporting Basis Adjustments (1) Group Reporting Basis Reclassi- fications (2) U.S. GAAP Consolidated Totals (in millions) Six Months Ended June 30, 2018 Net interest income $ 441 $ 381 $ 300 $ 90 $ 33 $ 1,245 $ 14 $ (152 ) $ 1,107 Other operating income 164 113 449 36 155 917 (20 ) 153 1,050 Total operating income 605 494 749 126 188 2,162 (6 ) 1 2,157 Expected credit losses / provision for credit losses 6 (46 ) (157 ) (3 ) 4 (196 ) 67 13 (116 ) 599 540 906 129 184 2,358 (73 ) (12 ) 2,273 Operating expenses 666 290 425 122 586 2,089 (9 ) (12 ) 2,068 Profit (loss) before income tax expense $ (67 ) $ 250 $ 481 $ 7 $ (402 ) $ 269 $ (64 ) $ — $ 205 Balances at end of period: Total assets $ 18,691 $ 23,851 $ 79,535 $ 7,075 $ 85,703 $ 214,855 $ (34,168 ) $ — $ 180,687 Total loans, net 16,695 22,879 17,786 6,036 1,865 65,261 (1,341 ) 1,948 65,868 Goodwill 581 358 — 321 — 1,260 347 — 1,607 Total deposits 32,672 23,643 32,749 8,112 4,553 101,729 (3,168 ) 15,794 114,355 (1) Represents adjustments associated with differences between U.S. GAAP and the Group Reporting Basis. (2) Represents differences in financial statement presentation between U.S. GAAP and the Group Reporting Basis.

Retained Earnings and Regulator

Retained Earnings and Regulatory Capital Requirements	6 Months Ended
	Jun. 30, 2019
Banking and Thrift [Abstract]
Retained Earnings and Regulatory Capital Requirements	Retained Earnings and Regulatory Capital Requirements Bank dividends are one of the sources of funds used for payment of shareholder dividends and other HSBC USA cash needs. Approval from the Office of the Comptroller of the Currency ("OCC") is required if the total of all dividends HSBC Bank USA declares in any year exceeds the cumulative net income for that year, combined with the net income for the two preceding years reduced by dividends attributable to those years. OCC approval also is required for a reduction of permanent capital of HSBC Bank USA. Under a separate restriction, payment of dividends is prohibited in amounts greater than undivided profits then on hand, after deducting actual losses and bad debts. Bad debts are debts due and unpaid for a period of six months unless well secured, as defined, and in the process of collection. In early 2019, HSBC Bank USA's Board of Directors approved a common stock return of capital of $2.4 billion to HSBC USA and HSBC USA's Board of Directors approved a distribution on its common stock of $2.4 billion from surplus capital to HSBC North America, which were paid in February 2019. HSBC Bank USA is also required to maintain reserve balances either in the form of vault cash or on deposit with the Federal Reserve Bank, based on a percentage of deposits. At June 30, 2019 and December 31, 2018 , HSBC Bank USA was required to maintain $2,343 million and $2,205 million , respectively, of reserve balances with the Federal Reserve Bank which are reported within interest bearing deposits with banks on the consolidated balance sheet. We are subject to regulatory capital rules issued by U.S. banking regulators including Basel III (the "Basel III rule"). The following table summarizes the capital amounts and ratios of HSBC USA and HSBC Bank USA, calculated in accordance with the Basel III rule at June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 Capital Amount Well-Capitalized Ratio (1) Actual Ratio Capital Amount Well-Capitalized Ratio (1) Actual Ratio (dollars are in millions) Common equity Tier 1 ratio: HSBC USA $ 15,678 4.5 % (2) 12.4 % $ 17,459 4.5 % (2) 13.6 % HSBC Bank USA 17,752 6.5 14.4 19,456 6.5 15.7 Tier 1 capital ratio: HSBC USA 16,943 6.0 13.4 18,724 6.0 14.6 HSBC Bank USA 20,252 8.0 16.5 21,956 8.0 17.7 Total capital ratio: HSBC USA 20,342 10.0 16.1 21,972 10.0 17.2 HSBC Bank USA 23,655 10.0 19.2 25,293 10.0 20.4 Tier 1 leverage ratio: HSBC USA 16,943 4.0 (2) 9.6 18,724 4.0 (2) 11.0 HSBC Bank USA 20,252 5.0 11.7 21,956 5.0 13.1 Supplementary leverage ratio ("SLR"): HSBC USA 16,943 3.0 (3) 6.8 18,724 3.0 (3) 7.6 HSBC Bank USA 20,252 3.0 (3) 8.3 21,956 3.0 (3) 9.1 Risk-weighted assets: (4) HSBC USA 126,416 127,917 HSBC Bank USA 123,021 124,112 Adjusted quarterly average assets: (5) HSBC USA 176,467 170,565 HSBC Bank USA 173,320 168,154 Total leverage exposure: (6) HSBC USA 248,581 245,796 HSBC Bank USA 243,943 242,264 (1) HSBC USA and HSBC Bank USA are categorized as "well-capitalized," as defined by their principal regulators. To be categorized as well-capitalized under regulatory guidelines, a banking institution must have the ratios reflected in the above table, and must not be subject to a directive, order, or written agreement to meet and maintain specific capital levels. (2) There are no common equity Tier 1 or Tier 1 leverage ratio components in the definition of a well-capitalized bank holding company. The ratios shown are the regulatory minimum ratios. (3) There is no SLR component in the definition of a well-capitalized banking institution. The ratios shown are the regulatory minimum ratios. (4) Calculated using the generally-applicable Standardized Approach. (5) Represents the Tier 1 leverage ratio denominator which reflects quarterly average assets adjusted for amounts permitted to be deducted from Tier 1 capital. (6) Represents the SLR denominator which includes adjusted quarterly average assets plus certain off-balance sheet exposures.

Variable Interest Entities

Variable Interest Entities	6 Months Ended
	Jun. 30, 2019
Variable Interest Entities [Abstract]
Variable Interest Entities	Variable Interest Entities In the ordinary course of business, we have organized special purpose entities ("SPEs") primarily to structure financial products to meet our clients' investment needs, to facilitate clients to access and raise financing from capital markets and to securitize financial assets held to meet our own funding needs. For disclosure purposes, we aggregate SPEs based on the purpose, risk characteristics and business activities of the SPEs. An SPE is a VIE if it lacks sufficient equity investment at risk to finance its activities without additional subordinated financial support or, as a group, the holders of the equity investment at risk lack either a) the power through voting or similar rights to direct the activities of the entity that most significantly impacts the entity's economic performance; or b) the obligation to absorb the entity's expected losses, the right to receive the expected residual returns, or both. Variable Interest Entities We consolidate VIEs in which we hold a controlling financial interest as evidenced by the power to direct the activities of a VIE that most significantly impact its economic performance and the obligation to absorb losses of, or the right to receive benefits from, the VIE that could potentially be significant to the VIE and therefore are deemed to be the primary beneficiary. We take into account our entire involvement in a VIE (explicit or implicit) in identifying variable interests that individually or in the aggregate could be significant enough to warrant our designation as the primary beneficiary and hence require us to consolidate the VIE or otherwise require us to make appropriate disclosures. We consider our involvement to be potentially significant where we, among other things, (i) enter into derivative contracts to absorb the risks and benefits from the VIE or from the assets held by the VIE; (ii) provide a financial guarantee that covers assets held or liabilities issued by a VIE; (iii) sponsor the VIE in that we design, organize and structure the transaction; and (iv) retain a financial or servicing interest in the VIE. We are required to evaluate whether to consolidate a VIE when we first become involved and on an ongoing basis. In almost all cases, a qualitative analysis of our involvement in the entity provides sufficient evidence to determine whether we are the primary beneficiary. In rare cases, a more detailed analysis to quantify the extent of variability to be absorbed by each variable interest holder is required to determine the primary beneficiary. Consolidated VIEs The following table summarizes assets and liabilities related to our consolidated VIEs at June 30, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. June 30, 2019 December 31, 2018 Consolidated Assets Consolidated Liabilities Consolidated Assets Consolidated Liabilities (in millions) Low income housing limited liability partnership: Other assets $ 98 $ — $ 112 $ — Long-term debt — 66 — 66 Interest, taxes and other liabilities — 32 — 37 Total $ 98 $ 98 $ 112 $ 103 Low income housing limited liability partnership In 2009, all low income housing investments held by us at the time were transferred to a Limited Liability Partnership ("LLP") in exchange for debt and equity while a third party invested cash for an equity interest that is mandatorily redeemable at a future date. The LLP was created in order to ensure the utilization of future tax benefits from these low income housing tax projects. The LLP was deemed to be a VIE as it does not have sufficient equity investment at risk to finance its activities. Upon entering into this transaction, we concluded that we are the primary beneficiary of the LLP due to the nature of our continuing involvement and, as a result, we consolidate the LLP and report the equity interest issued to the third party investor in other liabilities and the assets of the LLP in other assets on our consolidated balance sheet. The investments held by the LLP represent equity investments in the underlying low income housing partnerships. The LLP does not consolidate the underlying partnerships because it does not have the power to direct the activities of the partnerships that most significantly impact the economic performance of the partnerships. As a practical expedient, we amortize our low income housing investments in proportion to the allocated tax benefits under the proportional amortization method and present the associated tax benefits net of investment amortization in income tax expense. Unconsolidated VIEs We also have variable interests in other VIEs that are not consolidated because we are not the primary beneficiary. The following table provides additional information on these unconsolidated VIEs, including the variable interests held by us and our maximum exposure to loss arising from our involvements in these VIEs, at June 30, 2019 and December 31, 2018 : Total Assets Held by Unconsolidated VIEs Carrying Value of Variable Interests Held Reported as Maximum Exposure to Loss Assets Liabilities (in millions) At June 30, 2019 Structured note vehicles $ 1,526 $ 510 $ 11 $ 1,515 Limited partnership investments 2,037 542 260 570 Total $ 3,563 $ 1,052 $ 271 $ 2,085 At December 31, 2018 Structured note vehicles $ 3,033 $ 1,803 $ 20 $ 3,003 Limited partnership investments 1,578 454 209 454 Total $ 4,611 $ 2,257 $ 229 $ 3,457 Information on the types of VIEs with which we are involved, the nature of our involvement and the variable interests held in those entities is presented below. Structured note vehicles We provide derivatives, such as interest rate and currency swaps, to structured note vehicles and, in certain instances, invest in the vehicles' debt instruments. We hold variable interests in these structured note vehicles in the form of total return swaps under which we take on the risks and benefits of the structured notes they issue. The same risks and benefits are passed on to third party entities through back-end total return swaps. We earn a spread for facilitating the transaction. Since we do not have the power to direct the activities of the VIE and are not the primary beneficiary, we do not consolidate them. Our maximum exposure to loss is the notional amount of the derivatives wrapping the structured notes. The maximum exposure to loss of $1,515 million at June 30, 2019 will occur in the unlikely scenario where the value of the structured notes is reduced to zero and, at the same time, the counterparty of the back-end swap defaults with zero recovery. In certain instances, we hold credit default swaps with the structured note vehicles under which we receive credit protection on specified reference assets in exchange for the payment of a premium. Through these derivatives, the vehicles assume the credit risk associated with the reference assets which are then passed on to the holders of the debt instruments they issue. Because they create rather than absorb variability, the credit default swaps we hold are not considered variable interests. We record all investments in, and derivative contracts with, unconsolidated structured note vehicles at fair value on our consolidated balance sheet. During the first quarter of 2019, one of the structured note vehicles was unwound and our investment in the structured note vehicle along with the related derivatives were terminated. As a result, we recognized a loss of approximately $39 million , reflecting a payment made to the derivative counterparty as a result of the termination. At the time of unwind, our investment in the structured note vehicle had a total carrying value of $1,293 million , which was recorded in trading assets on the consolidated balance sheet. Limited partnership investments We invest as a limited partner in partnerships that operate qualified affordable housing, renewable energy and community development projects. The returns of these investments are generated primarily from the tax benefits, including Federal tax credits and tax deductions from operating losses in the project companies. In addition, some of the investments also help us comply with the Community Reinvestment Act. Certain limited partnership structures are considered to be VIEs because either (a) they do not have sufficient equity investment at risk or (b) the limited partners with equity at risk do not have substantive kick-out rights through voting rights or substantive participating rights over the general partner. As a limited partner, we are not the primary beneficiary of the VIEs and do not consolidate them. Our investments in these partnerships are recorded in other assets on the consolidated balance sheet. The maximum exposure to loss shown in the table above represents our recorded investments as well as any outstanding funding commitments extended to the partnerships. Third-party sponsored securitization entities We invest in asset-backed securities issued by third party sponsored securitization entities which may be considered VIEs. The investments are transacted at arm's-length and decisions to invest are based on a credit analysis of the underlying collateral assets or the issuer. We are a passive investor in these issuers and do not have the power to direct the activities of these issuers. As such, we do not consolidate these securitization entities. Additionally, we do not have other involvements in servicing or managing the collateral assets or provide financial or liquidity support to these issuers which potentially give rise to risk of loss exposure. These investments are an integral part of the disclosure in Note 2, "Trading Assets and Liabilities," Note 3, "Securities," and Note 19, "Fair Value Measurements," and, therefore, are not disclosed in this note to avoid redundancy.

Guarantee Arrangements, Pledged

Guarantee Arrangements, Pledged Assets and Repurchase Agreements	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Guarantee Arrangements, Pledged Assets and Repurchase Agreements	Guarantee Arrangements, Pledged Assets and Repurchase Agreements Guarantee Arrangements As part of our normal operations, we enter into credit derivatives and various off-balance sheet guarantee arrangements with affiliates and third parties. These arrangements arise principally in connection with our lending and client intermediation activities and include standby letters of credit and certain credit derivative transactions. The contractual amounts of these arrangements represent our maximum possible credit exposure in the event that we are required to fulfill the maximum obligation under the contractual terms of the guarantee. The following table presents total carrying value and contractual amounts of our sell protection credit derivatives and major off-balance sheet guarantee arrangements at June 30, 2019 and December 31, 2018 . Following the table is a description of the various arrangements. June 30, 2019 December 31, 2018 Carrying Value Notional / Maximum Exposure to Loss Carrying Value Notional / Maximum Exposure to Loss (in millions) Credit derivatives (1)(2) $ (268 ) $ 54,256 $ (562 ) $ 45,384 Financial standby letters of credit, net of participations (3)(4) — 5,376 — 5,302 Performance standby letters of credit, net of participations (3)(4) — 3,489 — 3,670 Total $ (268 ) $ 63,121 $ (562 ) $ 54,356 (1) Includes $32,481 million and $25,734 million of notional issued for the benefit of HSBC affiliates at June 30, 2019 and December 31, 2018 , respectively. (2) For credit derivatives, the maximum loss is represented by the notional amounts without consideration of mitigating effects from collateral or recourse arrangements. (3) Includes $1,419 million and $1,321 million of both financial and performance standby letters of credit issued for the benefit of HSBC affiliates at June 30, 2019 and December 31, 2018 , respectively. (4) For standby letters of credit, maximum loss represents losses to be recognized assuming the letters of credit have been fully drawn and the obligors have defaulted with zero recovery. Credit-Risk Related Guarantees Credit derivatives Credit derivatives are financial instruments that transfer the credit risk of a reference obligation from the credit protection buyer to the credit protection seller who is exposed to the credit risk without buying the reference obligation. We sell credit protection on underlying reference obligations (such as loans or securities) by entering into credit derivatives, primarily in the form of credit default swaps, with various institutions. We account for all credit derivatives at fair value. Where we sell credit protection to a counterparty that holds the reference obligation, the arrangement is effectively a financial guarantee on the reference obligation. Under a credit derivative contract, the credit protection seller will reimburse the credit protection buyer upon occurrence of a credit event (such as bankruptcy, insolvency, restructuring or failure to meet payment obligations when due) as defined in the derivative contract, in return for a periodic premium. Upon occurrence of a credit event, we will pay the counterparty the stated notional amount of the derivative contract and receive the underlying reference obligation. The recovery value of the reference obligation received could be significantly lower than its notional principal amount when a credit event occurs. Certain derivative contracts are subject to master netting arrangements and related collateral agreements. A party to a derivative contract may demand that the counterparty post additional collateral in the event its net exposure exceeds certain predetermined limits and when the credit rating falls below a certain grade. We set the collateral requirements by counterparty such that the collateral covers various transactions and products, and is not allocated to specific individual contracts. We manage our exposure to credit derivatives using a variety of risk mitigation strategies where we enter into offsetting hedge positions or transfer the economic risks, in part or in entirety, to investors through the issuance of structured credit products. We actively manage the credit and market risk exposure in the credit derivative portfolios on a net basis and, as such, retain no or a limited net position at any time. The following table summarizes our net credit derivative positions at June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 Carrying / Fair Value Notional Carrying / Fair Value Notional (in millions) Sell-protection credit derivative positions $ (268 ) $ 54,256 $ (562 ) $ 45,384 Buy-protection credit derivative positions 144 68,618 601 51,914 Net position (1) $ (124 ) $ 14,362 $ 39 $ 6,530 (1) Positions are presented net in the table above to provide a complete analysis of our risk exposure and depict the way we manage our credit derivative portfolio. The offset of the sell-protection credit derivatives against the buy-protection credit derivatives may not be legally binding in the absence of master netting agreements with the same counterparty. Furthermore, the credit loss triggering events for individual sell protection credit derivatives may not be the same or occur in the same period as those of the buy protection credit derivatives thereby not providing an exact offset. Standby letters of credit A standby letter of credit is issued to a third party for the benefit of a client and is a guarantee that the client will perform or satisfy certain obligations under a contract. It irrevocably obligates us to pay a specified amount to the third party beneficiary if the client fails to perform the contractual obligation. We issue two types of standby letters of credit: performance and financial. A performance standby letter of credit is issued where the client is required to perform some non-financial contractual obligation, such as the performance of a specific act, whereas a financial standby letter of credit is issued where the client's contractual obligation is of a financial nature, such as the repayment of a loan or debt instrument. The issuance of a standby letter of credit is subject to our credit approval process and collateral requirements. We charge fees for issuing letters of credit commensurate with the client's credit evaluation and the nature of any collateral. Included in other liabilities are deferred fees on standby letters of credit amounting to $47 million and $43 million at June 30, 2019 and December 31, 2018 , respectively. Also included in other liabilities is an allowance for credit losses on unfunded standby letters of credit of $17 million and $16 million at June 30, 2019 and December 31, 2018 , respectively. The following table summarizes the credit ratings related to guarantees including the ratings of counterparties against which we sold credit protection and financial standby letters of credit at June 30, 2019 as an indicative proxy of payment risk: Average Life (in years) Credit Ratings of the Obligors Notional/Contractual Amounts Investment Non-Investment Grade Total (dollars are in millions) Sell-protection Credit Derivatives (1) Single name credit default swaps ("CDS") 3.0 $ 27,275 $ 13,413 $ 40,688 Index credit derivatives 4.1 5,509 6,724 12,233 Total return swaps 2.2 1,073 262 1,335 Subtotal 33,857 20,399 54,256 Standby Letters of Credit (2) 1.1 7,185 1,680 8,865 Total $ 41,042 $ 22,079 $ 63,121 (1) The credit ratings in the table represent external credit ratings for classification as investment grade and non-investment grade. (2) External ratings for most of the obligors are not available. Presented above are the internal credit ratings which are developed using similar methodologies and rating scale equivalent to external credit ratings for purposes of classification as investment grade and non-investment grade. Our internal credit ratings are determined based on HSBC's risk rating systems and processes which assign a credit grade based on a scale which ranks the risk of default of a client. The credit grades are assigned and used for managing risk and determining level of credit exposure appetite based on the client's operating performance, liquidity, capital structure and debt service ability. In addition, we also incorporate subjective judgments into the risk rating process concerning such things as industry trends, comparison of performance to industry peers and perceived quality of management. We compare our internal risk ratings to outside external rating agency benchmarks, where possible, at the time of formal review and regularly monitor whether our risk ratings are comparable to the external ratings benchmark data. A non-investment grade rating of a referenced obligor has a negative impact to the fair value of the credit derivative and increases the likelihood that we will be required to perform under the credit derivative contract. We employ market-based parameters and, where possible, use the observable credit spreads of the referenced obligors as measurement inputs in determining the fair value of the credit derivatives. We believe that such market parameters are more indicative of the current status of payment/performance risk than external ratings by the rating agencies which may not be forward-looking in nature and, as a result, lag behind those market-based indicators. Non Credit-Risk Related Guarantees and Other Arrangements Visa covered litigation In 2008, we received Class B Shares as part of Visa's initial public offering ("IPO"). Pursuant to the IPO, we, along with all the other Class B shareholders, agreed to indemnify Visa for the claims and obligations arising from certain specific covered litigation. The Class B Shares are not eligible to be converted into publicly traded Class A Shares until settlement of the covered litigation described in Note 28, "Litigation and Regulatory Matters," in our 2018 Form 10-K. Accordingly, the Class B Shares are considered restricted and are only transferable under limited circumstances, which include transfers to other Class B shareholders. Beginning in 2016 and into 2017, we sold substantially all of our remaining Visa Class B Shares to a third party. Under the terms of the sale agreements, we entered into swap agreements with the purchaser to retain the litigation risk associated with the Class B Shares sold until the related litigation is settled and the Class B Shares can be converted into Class A Shares. These swaps had a carrying value of $40 million at both June 30, 2019 and December 31, 2018 , respectively. The swap agreements we entered into with the purchaser requires us to (a) make periodic payments, calculated by reference to the market price of Class A Shares and (b) make or receive payments based on subsequent changes in the conversion rate of Class B Shares into Class A Shares. In 2017, we entered into a total return swap position to economically hedge the periodic payments made under these swap agreements. The payments under the derivative will continue until the Class B Shares are able to be converted into Class A Shares. During the second quarter of 2018, we recorded a loss of $7 million related to a change in the Visa Class B Share conversion rate as a result of the outstanding litigation. The fair value of the swap agreements is estimated using a discounted cash flow methodology and is dependent upon the final resolution of the related litigation. Changes in fair value between periods are recognized in other income (loss). See Note 9, "Derivative Financial Instruments," for further information. Clearing houses and exchanges We are a member of various exchanges and clearing houses that trade and clear securities and/or derivatives contracts. Under the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, members of a clearing house may be required to contribute to a guaranty fund to backstop members' obligations to the clearing house. As a member, we may be required to pay a proportionate share of the financial obligations of another member who defaults on its obligations to the exchange or the clearing house. Our guarantee obligations would arise only if the exchange or clearing house had exhausted its resources. Any potential contingent liability under these membership agreements cannot be estimated. Lease Obligations We are obligated under a number of noncancellable operating leases for premises and equipment. See Note 8, "Leases," for a full discussion of our leases, including a maturity analysis of our operating lease liabilities. Mortgage Loan Repurchase Obligations We have provided various representations and warranties related to the origination and sale of mortgage loans including, among other things, the ownership of the loans, the validity of the liens, the loan selection and origination process, and the compliance to the origination criteria established by the government agencies. In the event of a breach of our representations and warranties, we may be obligated to repurchase the loans with identified defects or to indemnify the buyers. Our contractual obligation arises only when the breach of representations and warranties are discovered and repurchase is demanded. From 2013 to 2017, we sold agency-eligible mortgage loan originations directly to PHH Mortgage Corporation and they are responsible for origination representations and warranties for all such loans. With the insourcing of our mortgage fulfillment operations, beginning with 2018 applications, we are now responsible for origination representations and warranties for all agency-eligible mortgage loan originations sold to third parties. In estimating our repurchase liability arising from breaches of representations and warranties, we consider historical losses on residual risks not covered by settlement agreements adjusted for any risk factors not captured in the historical losses as well as the level of outstanding repurchase demands received. Outstanding repurchase demands received totaled $4 million and $2 million at June 30, 2019 and December 31, 2018 , respectively. The following table summarizes the change in our estimated repurchase liability during the three and six months ended June 30, 2019 and 2018 for obligations arising from the breach of representations and warranties associated with mortgage loans sold: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Balance at beginning of period $ 8 $ 10 $ 8 $ 10 Decrease in liability recorded through earnings (3 ) (1 ) (3 ) (1 ) Realized losses (1 ) — (1 ) — Balance at end of period $ 4 $ 9 $ 4 $ 9 Our repurchase liability of $4 million at June 30, 2019 represents our best estimate of the loss that has been incurred, including interest, arising from breaches of representations and warranties associated with mortgage loans sold. Because the level of mortgage loan repurchase losses is dependent upon economic factors, investor demand strategies and other external risk factors such as housing market trends that may change, the level of the liability for mortgage loan repurchase losses requires significant judgment. We continue to evaluate our methods of determining the best estimate of loss based on recent trends. As these estimates are influenced by factors outside our control, there is uncertainty inherent in these estimates making it reasonably possible that they could change. The range of reasonably possible losses in excess of our recorded repurchase liability is between zero and $25 million at June 30, 2019 . This estimated range of reasonably possible losses was determined based upon modifying the assumptions utilized in our best estimate of probable losses to reflect what we believe to be reasonably possible adverse assumptions. Securitization Activity In addition to the repurchase risk described above, we have also been involved as a sponsor/seller of loans used to facilitate whole loan securitizations underwritten by our affiliate, HSI. In this regard, we began acquiring residential mortgage loans in 2005 which were warehoused on our balance sheet with the intent of selling them to HSI to facilitate HSI's whole loan securitization program which was discontinued in 2007. During 2005-2007, we purchased and sold $24 billion of such loans to HSI which were subsequently securitized and sold by HSI to third parties. See "Mortgage Securitization Matters" in Note 28, "Litigation and Regulatory Matters," in our 2018 Form 10-K for additional discussion of related exposure. The outstanding principal balance on these loans was approximately $3.6 billion and $3.8 billion at June 30, 2019 and December 31, 2018 , respectively. Pledged Assets Pledged assets included in the consolidated balance sheet consisted of the following: June 30, 2019 December 31, 2018 (in millions) Interest bearing deposits with banks $ 2,762 $ 3,225 Trading assets (1) 7,429 2,465 Securities available-for-sale (2) 9,048 7,440 Securities held-to-maturity (2) 2,718 1,747 Loans (3) 17,371 18,189 Other assets (4) 2,515 2,289 Total $ 41,843 $ 35,355 (1) Trading assets are primarily pledged against liabilities associated with repurchase agreements. (2) Securities are primarily pledged against derivatives, public fund deposits, trust deposits and various short-term and long term borrowings, as well as providing capacity for potential secured borrowings from the FHLB and the Federal Reserve Bank of New York. (3) Loans are primarily residential mortgage loans pledged against current and potential borrowings from the FHLB and the Federal Reserve Bank of New York. (4) Other assets represent cash on deposit with non-banks related to derivative collateral support agreements. Debt securities pledged as collateral under repurchase agreements that can be sold or repledged by the secured party continue to be reported on the consolidated balance sheet. The fair value of securities available-for-sale that could be sold or repledged was $2,290 million and $822 million at June 30, 2019 and December 31, 2018 , respectively. The fair value of trading assets that could be sold or repledged was $7,402 million and $2,464 million at June 30, 2019 and December 31, 2018 , respectively. The fair value of collateral we accepted under security resale agreements but was not reported on the consolidated balance sheet was $12,205 million and $13,004 million at June 30, 2019 and December 31, 2018 , respectively. Of this collateral, $11,255 million and $11,904 million could be sold or repledged at June 30, 2019 and December 31, 2018 , respectively, of which $436 million and $243 million , respectively, had been sold or repledged as collateral under repurchase agreements or to cover short sales. Repurchase Agreements We enter into purchases of securities under agreements to resell (resale agreements) and sales of securities under agreements to repurchase (repurchase agreements) identical or substantially the same securities. Resale and repurchase agreements are accounted for as secured lending and secured borrowing transactions, respectively. Repurchase agreements may require us to deposit cash or other collateral with the lender. In connection with resale agreements, it is our policy to obtain possession of collateral, which may include the securities purchased, with market value in excess of the principal amount loaned. The market value of the collateral subject to the resale and repurchase agreements is regularly monitored, and additional collateral is obtained or provided when appropriate, to ensure appropriate collateral coverage of these secured financing transactions. The following table provides information about resale and repurchase agreements that are subject to offset at June 30, 2019 and December 31, 2018 : Gross Amounts Not Offset in the Balance Sheet Gross Amounts Recognized Gross Amounts Offset in the Balance Sheet (1) Net Amounts Presented in the Balance Sheet Financial Instruments (2) Cash Collateral Received / Pledged Net Amount (3) (in millions) At June 30, 2019 Assets: Securities purchased under resale agreements $ 11,602 $ 6,313 $ 5,289 $ 5,287 $ — $ 2 Liabilities: Securities sold under repurchase agreements $ 9,866 $ 6,313 $ 3,553 $ 3,553 $ — $ — At December 31, 2018 Assets: Securities purchased under resale agreements $ 12,035 $ 1,867 $ 10,168 $ 10,165 $ — $ 3 Liabilities: Securities sold under repurchase agreements $ 3,333 $ 1,867 $ 1,466 $ 1,458 $ — $ 8 (1) Represents recognized amount of resale and repurchase agreements with counterparties subject to legally enforceable netting agreements that meet the applicable netting criteria as permitted by generally accepted accounting principles. (2) Represents securities received or pledged to cover financing transaction exposures. (3) Represents the amount of our exposure that is not collateralized / covered by pledged collateral. The following table provides the class of collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings at June 30, 2019 and December 31, 2018 : Overnight and Continuous Up to 30 Days 31 to 90 Days 91 Days to One Year Greater Than One Year Total (in millions) At June 30, 2019 U.S. Treasury, U.S. Government sponsored and U.S. Government agency securities $ 7,075 $ 1,644 $ — $ 500 $ 500 $ 9,719 Foreign debt securities — 147 — — — 147 Total repurchase agreements accounted for as secured borrowings $ 7,075 $ 1,791 $ — $ 500 $ 500 $ 9,866 At December 31, 2018 U.S. Treasury, U.S. Government sponsored and U.S. Government agency securities $ 1,773 $ 369 $ — $ 191 $ 1,000 $ 3,333

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Accounting principles related to fair value measurements provide a framework for measuring fair value that focuses on the exit price that would be received to sell an asset or paid to transfer a liability in the principal market (or in the absence of the principal market, the most advantageous market) accessible in an orderly transaction between willing market participants (the "Fair Value Framework"). Where required by the applicable accounting standards, assets and liabilities are measured at fair value using the "highest and best use" valuation premise. Fair value measurement guidance clarifies that financial instruments do not have alternative use and, as such, the fair value of financial instruments should be determined using an "in-exchange" valuation premise. However, the fair value measurement literature provides a valuation exception and permits an entity to measure the fair value of a group of financial assets and financial liabilities with offsetting credit risks and/or market risks based on the exit price it would receive or pay to transfer the net risk exposure of a group of assets or liabilities if certain conditions are met. We elected to apply the measurement exception to a group of derivative instruments with offsetting credit risks and market risks, which primarily relate to interest rate, foreign currency, debt and equity price risk, and commodity price risk as of the reporting date. Fair Value Adjustments The best evidence of fair value is quoted market price in an actively traded market, where available. In the event listed price or market quotes are not available, valuation techniques that incorporate relevant transaction data and market parameters reflecting the attributes of the asset or liability under consideration are applied. Where applicable, fair value adjustments are made to ensure the financial instruments are appropriately recorded at fair value. The fair value adjustments reflect the risks associated with the products, contractual terms of the transactions, and the liquidity of the markets in which the transactions occur. The fair value adjustments are broadly categorized by the following major types: Credit valuation adjustment - The credit valuation adjustment is an adjustment to a group of financial assets and financial liabilities, predominantly derivative assets and derivative liabilities, to reflect the credit quality of the parties to the transaction in arriving at fair value. A credit valuation adjustment to a financial asset is required to reflect the default risk of the counterparty. A debit valuation adjustment to a financial liability is recorded to reflect the default risk of HUSI. See "Valuation Techniques - Derivatives" below for additional details. Liquidity risk adjustment - The liquidity risk adjustment (primarily in the form of bid-offer adjustment) reflects the cost that would be incurred to close out the market risks by hedging, disposing or unwinding the position. Valuation models generally produce mid-market values. The bid-offer adjustment is made in such a way that results in a measure that reflects the exit price that most represents the fair value of the financial asset or financial liability under consideration or, where applicable, the fair value of the net market risk exposure of a group of financial assets or financial liabilities. These adjustments relate primarily to Level 2 assets. Model valuation adjustment - Where fair value measurements are determined using an internal valuation model based on observable and unobservable inputs, certain valuation inputs may be less readily determinable. There may be a range of possible valuation inputs that market participants may assume in determining the fair value measurement. The resultant fair value measurement has inherent measurement risk if one or more parameters are unobservable and must be estimated. An input valuation adjustment is necessary to reflect the likelihood that market participants may use different input parameters, and to mitigate the possibility of measurement error. In addition, the values derived from valuation techniques are affected by the choice of valuation model and model limitation. When different valuation techniques are available, the choice of valuation model can be subjective. Furthermore, the valuation model applied may have measurement limitations. In those cases, an additional valuation adjustment is also applied to mitigate the measurement risk. Model valuation adjustments are not material and relate primarily to Level 2 instruments. We apply stress scenarios in determining appropriate liquidity risk and model risk adjustments for Level 3 fair values by reviewing the historical data for unobservable inputs (e.g., correlation, volatility). Some stress scenarios involve at least a 95 percent confidence interval (i.e., two standard deviations). We also utilize unobservable parameter adjustments when instruments are valued using internally developed models which reflects the uncertainty in the value estimates provided by the model. Funding Fair Value Adjustment ("FFVA") - The FFVA reflects the estimated present value of the future market funding cost or benefit associated with funding uncollateralized derivative exposure at rates other than the Overnight Indexed Swap ("OIS") rate. See "Valuation Techniques - Derivatives" below for additional details. Fair Value Hierarchy The Fair Value Framework establishes a three-tiered fair value hierarchy as follows: Level 1 quoted market price - Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 valuation technique using observable inputs - Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are inactive, and measurements determined using valuation models where all significant inputs are observable, such as interest rates and yield curves that are observable at commonly quoted intervals. Level 3 valuation technique with significant unobservable inputs - Level 3 inputs are unobservable inputs for the asset or liability and include situations where fair values are measured using valuation techniques based on one or more significant unobservable inputs. Classification within the fair value hierarchy is based on whether the lowest hierarchical level input that is significant to the fair value measurement is observable. As such, the classification within the fair value hierarchy is dynamic and can be transferred to other hierarchy levels in each reporting period. Where fair value measurements are determined based on information obtained from independent pricing services or brokers, Finance applies appropriate validation procedures to substantiate fair value. For price validation purposes, quotations from at least two independent pricing sources are obtained for each financial instrument, where possible. The following factors are considered in determining fair values: • similarities between the asset or the liability under consideration and the asset or liability for which quotation is received; • collaboration of pricing by referencing to other independent market data such as market transactions and relevant benchmark indices; • consistency among different pricing sources; • the valuation approach and the methodologies used by the independent pricing sources in determining fair value; • the elapsed time between the date to which the market data relates and the measurement date; • the source of the fair value information; and • whether the security is traded in an active or inactive market. Greater weight is given to quotations of instruments with recent market transactions, pricing quotes from dealers who stand ready to transact, quotations provided by market-makers who structured such instrument and market consensus pricing based on inputs from a large number of survey participants. Any significant discrepancies among the external quotations are reviewed and adjustments to fair values are recorded where appropriate. Where the transaction volume of a specific instrument has been reduced and the fair value measurement becomes less transparent, Finance will apply more detailed procedures to understand and challenge the appropriateness of the unobservable inputs and the valuation techniques used by the independent pricing service. Where applicable, Finance will develop a fair value estimate using its own pricing model inputs to test reasonableness. Where fair value measurements are determined using internal valuation models, Finance will validate the fair value measurement by either developing unobservable inputs based on the industry consensus pricing surveys in which we participate or back testing by observing the actual settlements occurring soon after the measurement date. Assets and Liabilities Recorded at Fair Value on a Recurring Basis The following table presents information about our assets and liabilities measured at fair value on a recurring basis at June 30, 2019 and December 31, 2018 , and indicates the fair value hierarchy of the valuation techniques utilized to determine such fair value. Unless otherwise noted below, assets and liabilities in the following table are recorded at fair value through net income. Fair Value Measurements on a Recurring Basis June 30, 2019 Level 1 Level 2 Level 3 Gross Balance Netting (7) Net Balance (in millions) Assets: Trading assets, excluding derivatives: U.S. Treasury, U.S. Government agencies and sponsored enterprises $ 10,620 $ 78 $ — $ 10,698 $ — $ 10,698 Asset-backed securities: Collateralized debt obligations — — 86 86 — 86 Residential mortgages — — 16 16 — 16 Student loans — — 90 90 — 90 Corporate and other domestic debt securities — — 510 510 — 510 Debt securities issued by foreign entities 12,199 216 — 12,415 — 12,415 Equity securities 2,747 — — 2,747 — 2,747 Precious metals trading — 3,895 — 3,895 — 3,895 Derivatives: (1) Interest rate contracts 99 11,450 11 11,560 — 11,560 Foreign exchange contracts 1 13,362 7 13,370 — 13,370 Equity contracts 16 3,575 185 3,776 — 3,776 Precious metals contracts 106 1,254 — 1,360 — 1,360 Credit contracts — 1,051 68 1,119 — 1,119 Other contracts (2) — — 5 5 — 5 Derivatives netting — — — — (27,994 ) (27,994 ) Total derivatives 222 30,692 276 31,190 (27,994 ) 3,196 Securities available-for-sale: (3) U.S. Treasury, U.S. Government agencies and sponsored enterprises 19,559 14,571 — 34,130 — 34,130 Asset-backed securities: Home equity — 36 — 36 — 36 Other — — 113 113 — 113 Debt securities issued by foreign entities 2,591 384 — 2,975 — 2,975 Loans (4) — 128 — 128 — 128 Other assets: Equity securities — 193 — 193 — 193 Equity Securities measured at net asset value (5) — — — 109 — 109 Other (6) — — 1 1 — 1 Total assets $ 47,938 $ 50,193 $ 1,092 $ 99,332 $ (27,994 ) $ 71,338 Liabilities: Domestic deposits (4) $ — $ 7,525 $ 930 $ 8,455 $ — $ 8,455 Trading liabilities, excluding derivatives 834 106 — 940 — 940 Derivatives: (1) Interest rate contracts 51 12,752 1 12,804 — 12,804 Foreign exchange contracts — 13,044 8 13,052 — 13,052 Equity contracts — 2,778 123 2,901 — 2,901 Precious metals contracts 137 1,254 — 1,391 — 1,391 Credit contracts — 1,253 22 1,275 — 1,275 Other contracts (2) — — 40 40 — 40 Derivatives netting — — — — (28,182 ) (28,182 ) Total derivatives 188 31,081 194 31,463 (28,182 ) 3,281 Short-term borrowings (4) — 222 — 222 — 222 Long-term debt (4) — 11,538 441 11,979 — 11,979 Total liabilities $ 1,022 $ 50,472 $ 1,565 $ 53,059 $ (28,182 ) $ 24,877 Fair Value Measurements on a Recurring Basis December 31, 2018 Level 1 Level 2 Level 3 Gross Balance Netting (7) Net Balance (in millions) Assets: Trading assets, excluding derivatives: U.S. Treasury, U.S. Government agencies and sponsored enterprises $ 5,368 $ 152 $ — $ 5,520 $ — $ 5,520 Asset-backed securities: Collateralized debt obligations — — 100 100 — 100 Residential mortgages — — 16 16 — 16 Student loans — — 92 92 — 92 Corporate and other domestic debt securities — — 1,803 1,803 — 1,803 Debt securities issued by foreign entities 8,552 207 — 8,759 — 8,759 Equity securities 751 — — 751 — 751 Precious metals trading — 1,889 — 1,889 — 1,889 Derivatives: (1) Interest rate contracts 2 10,053 2 10,057 — 10,057 Foreign exchange contracts — 15,919 2 15,921 — 15,921 Equity contracts — 2,449 97 2,546 — 2,546 Precious metals contracts 16 829 — 845 — 845 Credit contracts — 883 73 956 — 956 Other contracts (2) — — 5 5 — 5 Derivatives netting — — — — (27,192 ) (27,192 ) Total derivatives 18 30,133 179 30,330 (27,192 ) 3,138 Securities available-for-sale: (3) U.S. Treasury, U.S. Government agencies and sponsored enterprises 16,198 11,699 — 27,897 — 27,897 Asset-backed securities: Home equity — 42 — 42 — 42 Other — — 107 107 — 107 Debt securities issued by foreign entities 2,362 971 — 3,333 — 3,333 Loans (4) — 109 — 109 — 109 Other assets: Equity securities — 190 — 190 — 190 Equity Securities measured at net asset value (5) — — — 88 — 88 Other assets (6) — — 4 4 — 4 Total assets $ 33,249 $ 45,392 $ 2,301 $ 81,030 $ (27,192 ) $ 53,838 Liabilities: Domestic deposits (4) $ — $ 7,229 $ 925 $ 8,154 $ — $ 8,154 Trading liabilities, excluding derivatives 738 215 — 953 — 953 Derivatives: (1) Interest rate contracts 45 11,140 — 11,185 — 11,185 Foreign exchange contracts 15 15,715 3 15,733 — 15,733 Equity contracts — 2,717 149 2,866 — 2,866 Precious metals contracts 274 626 — 900 — 900 Credit contracts — 926 21 947 — 947 Other contracts (2) — — 40 40 — 40 Derivatives netting — — — — (28,847 ) (28,847 ) Total derivatives 334 31,124 213 31,671 (28,847 ) 2,824 Short-term borrowings (4) — 560 — 560 — 560 Long-term debt (4) — 10,837 412 11,249 — 11,249 Total liabilities $ 1,072 $ 49,965 $ 1,550 $ 52,587 $ (28,847 ) $ 23,740 (1) Includes trading derivative assets of $3,045 million and $3,048 million and trading derivative liabilities of $3,086 million and $2,690 million at June 30, 2019 and December 31, 2018 , respectively, as well as derivatives held for hedging and commitments accounted for as derivatives. See Note 9, "Derivative Financial Instruments," for additional information. Excluding changes in fair value of a derivative instrument associated with a qualifying cash flow hedge, which are recognized initially in other comprehensive income (loss), derivative assets and liabilities are recorded at fair value through net income. (2) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares. (3) Securities available-for-sale are recorded at fair value through other comprehensive income (loss). (4) See Note 10, "Fair Value Option," for additional information. Excluding the fair value movement on fair value option liabilities attributable to our own credit spread, which is recorded in other comprehensive income (loss), fair value option assets and liabilities are recorded at fair value through net income. (5) Investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy. (6) Represents contingent consideration receivable associated with the sale of a portion of our PB business. (7) Represents counterparty and cash collateral netting which allow the offsetting of amounts relating to certain contracts if certain conditions are met. Information on Level 3 assets and liabilities The following table summarizes additional information about changes in the fair value of Level 3 assets and liabilities during the three and six months ended June 30, 2019 and 2018 . As a risk management practice, we may risk manage the Level 3 assets and liabilities, in whole or in part, using securities and derivative positions that are classified as Level 1 or Level 2 measurements within the fair value hierarchy. Since those Level 1 and Level 2 risk management positions are not included in the table below, the information provided does not reflect the effect of such risk management activities related to the Level 3 assets and liabilities. Apr. 1, 2019 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2019 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 90 $ 2 $ — $ — $ — $ (6 ) $ — $ — $ 86 $ (4 ) Residential mortgage asset-backed securities 16 — — — — — — — 16 — Student loan asset-backed securities 95 — — — — (5 ) — — 90 (5 ) Corporate and other domestic debt securities 510 — — — — — — — 510 — Derivatives, net: (2) Interest rate contracts 7 8 — — — — — (5 ) 10 3 Foreign exchange contracts (1 ) — — — — — — — (1 ) — Equity contracts 24 39 — — — 1 — (2 ) 62 40 Credit contracts 53 (3 ) — — — (4 ) — — 46 (2 ) Other contracts (3) (37 ) (3 ) — — — 5 — — (35 ) — Other asset-backed securities available-for-sale (4) 109 — 4 — — — — — 113 4 Other assets (5) 1 — — — — — — — 1 — Total assets $ 867 $ 43 $ 4 $ — $ — $ (9 ) $ — $ (7 ) $ 898 $ 36 Liabilities: Domestic deposits (6) $ (949 ) $ (35 ) $ 2 $ — $ (49 ) $ 64 $ (5 ) $ 42 $ (930 ) $ (30 ) Long-term debt (6) (453 ) (15 ) 1 — (33 ) 20 — 39 (441 ) (9 ) Total liabilities $ (1,402 ) $ (50 ) $ 3 $ — $ (82 ) $ 84 $ (5 ) $ 81 $ (1,371 ) $ (39 ) Jan. 1, 2019 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2019 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 100 $ 3 $ — $ — $ — $ (17 ) $ — $ — $ 86 $ (10 ) Residential mortgage asset-backed securities 16 — — — — — — — 16 — Student loan asset-backed securities 92 5 — — — (7 ) — — 90 (2 ) Corporate and other domestic debt securities 1,803 — — — — (1,293 ) — — 510 — Derivatives, net: (2) Interest rate contracts 2 13 — — — — — (5 ) 10 8 Foreign exchange contracts (1 ) — — — — — — — (1 ) — Equity contracts (52 ) 110 — — — 5 — (1 ) 62 115 Credit contracts 52 (40 ) — — — 34 — — 46 (2 ) Other contracts (3) (35 ) (9 ) — — — 9 — — (35 ) — Other asset-backed securities available-for-sale (4) 107 — 6 — — — — — 113 6 Other assets (5) 4 — — — — (3 ) — — 1 — Total assets $ 2,088 $ 82 $ 6 $ — $ — $ (1,272 ) $ — $ (6 ) $ 898 $ 115 Liabilities: Domestic deposits (6) $ (925 ) $ (64 ) $ (3 ) $ — $ (145 ) $ 109 $ (5 ) $ 103 $ (930 ) $ (135 ) Long-term debt (6) (412 ) (43 ) (2 ) — (64 ) 33 — 47 (441 ) (61 ) Total liabilities $ (1,337 ) $ (107 ) $ (5 ) $ — $ (209 ) $ 142 $ (5 ) $ 150 $ (1,371 ) $ (196 ) Apr. 1, 2018 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2018 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 131 $ 1 $ — $ — $ — $ (1 ) $ — $ — $ 131 $ 1 Corporate and other domestic debt securities 1,803 — — — — — — — 1,803 — Derivatives, net: (2) Foreign exchange contracts — (1 ) — — — — — — (1 ) (1 ) Equity contracts 27 (10 ) — — — (16 ) (1 ) 2 2 (7 ) Credit contracts 113 1 — — — (4 ) — — 110 (3 ) Other contracts (3) (44 ) (12 ) — — — 5 — — (51 ) — Other asset-backed securities available-for-sale (4) 107 — — — — — — — 107 — Other assets (5) 15 (3 ) — — — — — — 12 — Total assets $ 2,152 $ (24 ) $ — $ — $ — $ (16 ) $ (1 ) $ 2 $ 2,113 $ (10 ) Liabilities: Domestic deposits (6) $ (916 ) $ 2 $ 5 $ — $ (88 ) $ 38 $ (10 ) $ 93 $ (876 ) $ 8 Long-term debt (6) (630 ) (5 ) 1 — (28 ) 74 — 31 (557 ) 1 Total liabilities $ (1,546 ) $ (3 ) $ 6 $ — $ (116 ) $ 112 $ (10 ) $ 124 $ (1,433 ) $ 9 Jan. 1, 2018 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2018 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 129 $ 8 $ — $ — $ — $ (6 ) $ — $ — $ 131 $ 8 Corporate and other domestic debt securities 1,803 — — — — — — — 1,803 — Derivatives, net: (2) Foreign exchange contracts — (1 ) — — — — — — (1 ) (1 ) Equity contracts 81 (50 ) — — — (30 ) (1 ) 2 2 (45 ) Credit contracts 114 2 — — — (6 ) — — 110 (4 ) Other contracts (3) (46 ) (14 ) — — — 9 — — (51 ) — Other asset-backed securities available-for-sale (4) 111 — (4 ) — — — — — 107 (4 ) Other assets (5) 15 (3 ) — — — — — — 12 — Total assets $ 2,207 $ (58 ) $ (4 ) $ — $ — $ (33 ) $ (1 ) $ 2 $ 2,113 $ (46 ) Liabilities: Domestic deposits (6) $ (897 ) $ 23 $ 3 $ — $ (179 ) $ 60 $ (13 ) $ 127 $ (876 ) $ 25 Long-term debt (6) (641 ) 6 5 — (143 ) 141 — 75 (557 ) 18 Total liabilities $ (1,538 ) $ 29 $ 8 $ — $ (322 ) $ 201 $ (13 ) $ 202 $ (1,433 ) $ 43 (1) Gains (losses) on trading assets, excluding derivatives are included in trading revenue in the consolidated statement of income. (2) Level 3 net derivatives included derivative assets of $276 million and derivative liabilities of $194 million at June 30, 2019 and derivative assets of $253 million and derivative liabilities of $193 million at June 30, 2018 . Gains (losses) on derivatives, net are predominantly included in trading revenue and gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income. (3) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares. Gains (losses) on these swap agreements are included in other income (loss) in the consolidated statement of income. (4) Realized gains (losses) on securities available-for-sale are included in other securities gains, net in the consolidated statement of income. Unrealized gains (losses) on securities available-for-sale are included in other comprehensive income (loss). (5) Represents contingent consideration receivable associated with the sale of a portion of our PB business. Gains (losses) associated with this transaction are included in other income (loss) in the consolidated statement of income. (6) Excluding unrealized gains (losses) on fair value option liabilities attributable to our own credit spread, which are recorded in other comprehensive income (loss), gains (losses) on fair value option liabilities are included in gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income. The following table presents quantitative information about the unobservable inputs used to determine the recurring fair value measurement of assets and liabilities classified as Level 3 fair value measurements at June 30, 2019 and December 31, 2018 : June 30, 2019 Financial Instrument Type Fair Value (in millions) Valuation Technique(s) Significant Unobservable Inputs Range of Inputs Collateralized debt obligations $ 86 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 0% - 1% Conditional default rates 0% - 1% Loss severity rates 90% - 95% Residential mortgage asset-backed securities $ 16 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 5% - 10% Conditional default rates 1% - 5% Loss severity rates 65% - 70% Discount margin 100bps - 250bps Student loan asset-backed securities $ 90 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 7% - 9% Conditional default rates 0% - 1% Loss severity rates 25% - 40% Discount margin 95bps -198bps Corporate and other domestic debt securities $ 510 Discounted cash flows Spread volatility on collateral assets 2% - 4% Correlation between insurance claim 80% Interest rate derivative contracts $ 10 Market comparable adjusted for probability to fund and, where applicable, discounted cash flows Probability to fund for rate lock commitments 38% - 96% Likelihood of transaction being executed 75% - 100% Foreign exchange derivative contracts (1) $ (1 ) Option pricing model Implied volatility of currency pairs 9% - 13% Equity derivative contracts (1) $ 62 Option pricing model Equity / Equity Index volatility 7% - 38% Equity / Equity and Equity / Index correlation 26% - 79% Equity dividend yields 0% - 4% Credit derivative contracts $ 46 Option pricing model and, where applicable, discounted cash flows Credit default swap spreads 49bps - 63bps Other derivative contracts $ (35 ) Discounted cash flows Conversion rate 1.6 times Expected duration 1 - 2 years Other asset-backed securities available-for-sale $ 113 Discounted cash flows Market assumptions related to yields for comparable instruments 1% - 3% Other assets $ 1 Discounted cash flows Client transfer rates based on rating 50% - 95% Domestic deposits (structured deposits) (1)(2) $ (930 ) Option adjusted discounted cash flows Implied volatility of currency pairs 9% - 13% Equity / Equity Index volatility 7% - 29% Equity / Equity and Equity / Index correlation 43% - 46% Long-term debt (structured notes) (1)(2) $ (441 ) Option adjusted discounted cash flows Implied volatility of currency pairs 9% - 13% Equity / Equity Index volatility 7% - 33% Equity / Equity and Equity / Index correlation 26% - 79% December 31, 2018 Financial Instrument Type Fair Value (in millions) Valuation Technique(s) Significant Unobservable Inputs Range of Inputs Collateralized debt obligations $ 100 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 0% - 1% Conditional default rates 0% - 1% Loss severity rates 90% - 95% Residential mortgage asset-backed securities $ 16 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 0% - 5% Conditional default rates 1% - 4% Loss severity rates 80% - 85% Discount margin 100bps - 250bps Student loan asset-backed securities $ 92 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 6% - 7% Conditional default rates 1% - 2% Loss severity rates 25% - 40% Discount margin 91bps -115bps Corporate and other domestic debt securities $ 1,803 Discounted cash flows Spread volatility on collateral assets 2% - 4% Correlation between insurance claim shortfall and collateral value 80% Interest rate derivative contracts $ 2 Market comparable adjusted for probability to fund and, where applicable, discounted cash flows Probability to fund for rate lock commitments 3% - 99% Likelihood of transaction being executed 75% - 100% Foreign exchange derivative contracts (1) $ (1 ) Option pricing model Implied volatility of currency pairs 8% - 12% Equity derivative contracts (1) $ (52 ) Option pricing model Equity / Equity Index volatility 7% - 44% Equity / Equity and Equity / Index correlation 42% - 79% Equity dividend yields 0% - 7% Credit derivative contracts $ 52 Option pricing model and, where applicable, discounted cash flows Credit default swap spreads 102bps - 118bps Other derivative contracts $ (35 ) Discounted cash flows Conversion rate 1.6 times Expected duration 2 - 3 years Other asset-backed securities available-for-sale $ 107 Discounted cash flows Market assumptions related to yields for comparable instruments 1% - 3% Other assets $ 4 Discounted cash flows Client transfer rates based on rating 50% - 95% Domestic deposits (structured deposits) (1)(2) $ (925 ) Option adjusted discounted cash flows Implied volatility of currency pairs 8% - 12% Equity / Equity Index volatility 7% - 37% Equity / Equity and Equity / Index correlation 42% - 49% Long-term debt (structured notes) (1)(2) $ (412 ) Option adjusted discounted cash flows Implied volatility of currency pairs 8% - 12% Equity / Equity Index volatility 7% - 42% Equity / Equity and Equity / Index correlation 45% - 79% (1) We are the client-facing entity and we enter into identical but opposite derivatives to transfer the resultant risks to our affiliates. With the exception of counterparty credit risks, we are market neutral. The corresponding intra-group derivatives are presented as equity derivatives and foreign exchange derivatives in the table. (2) Structured deposits and structured notes contain embedded derivative features whose fair value measurements contain significant Level 3 inputs. Significant Unobservable Inputs for Recurring Fair Value Measurements Collateralized debt obligations ("CDOs"), residential mortgage asset-backed securities and student loan asset-backed securities • Prepayment rate - The rate at which borrowers pay off the loans early. The prepayment rate is affected by a number of factors including location of the collateral, interest rate type of the loan, borrowers' credit and sensitivity to interest rate movement. The weighted average prepayment rates of our CDOs, residential mortgage asset-backed securities and student loan asset-backed securities was 0.4 percent , 5 percent and 8 percent , respectively, at June 30, 2019 . • Default rate - Annualized percentage of default rate over a group of collateral such as residential or commercial mortgage loans. The default rate and loss severity rate are positively correlated. The weighted average default rates of our CDOs, residential mortgage asset-backed securities and student loan asset-backed securities was 0.9 percent , 5 percent and 0.8 percent , respectively, at June 30, 2019 . • Loss severity rate - The loss severity rate is the percentage of total lifetime losses (both interest and principal) as a percentage of principal balance measured at default date. The weighted average loss severity rates of our CDOs, residential mortgage asset-backed securities and student loan asset-backed securities was 93 percent , 65 percent and 36 percent , respectively, at June 30, 2019 . • Discount margin - An expected return earned in addition to the index underlying (in this case the London Interbank Offered Rate ("LIBOR")) is another input into valuation of securities. The weighted average discount margins of our residential mortgage asset-backed securities and student loan asset-backed securities was 200 basis points and 122 basis points , respectively, at June 30, 2019 . Derivatives • Implied volatility - The implied volatility is a significant pricing input for freestanding or embedded options including equity, foreign currency and interest rate options. The level of volatility is a function of the nature of the underlying risk, the level of strike price and the years to maturity of the option. Depending on the underlying risk and tenure, we determine the implied volatility based on observable input where information is available. However, substantially all of the implied volatilities are derived based on historical information. The implied volatility for different foreign currency pairs is between 9 percent and 13 percent while the implied volatility for equity/equity or equity/equity index is between 7 percent and 38 percent , respectively, at June 30, 2019 . Although implied foreign currency volatility and equity volatility appear to be widely distributed at the portfolio level, the deviation of implied volatility on a trade-by-trade basis is narrower. The average deviation of implied volatility for the foreign currency pair and at-the-money equity option are 2 percent and 6 percent , respectively, at June 30, 2019 . • Correlations of a group of foreign currency or equity - Correlation measures the relative change in values among two or more variables (i.e., equity or foreign currency pair). Variables can be positively or negatively correlated. Correlation is a key input in determining the fair value of a derivative referenced to a basket of variables such as equities or foreign currencies. A majority of the correlations are not observable, but are derived based on historical data. The correlation between equity/equity and equity/equity index was between 26 percent and 79 percent at June 30, 2019 . Uncertainty of Level 3 Inputs to Fair Value Measurements CDOs - Probability of default, prepayment speed and loss severity rate are significant unobservable inputs. A significant increase (decrease) in these inputs would have resulted in a lower (higher) fair value measurement of the CDOs. Generally, a change in assumption for default probability would have been accompanied by a directionally similar change in loss severity, and a directionally opposite change in prepayment speed. Residential mortgage and student loan asset-backed securities - Probability of default, prepayment speed, loss severity rate and discount margin are significant unobservable inp

Litigation and Regulatory Matte

Litigation and Regulatory Matters	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Litigation and Regulatory Matters	Litigation and Regulatory Matters The following supplements, and should be read together with, the disclosure in Note 28, "Litigation and Regulatory Matters," in our 2018 Form 10-K and in Note 20, "Litigation and Regulatory Matters," in our Form 10-Q for the three month period ended March 31, 2019 (the "2019 First Quarter Form 10-Q"). Only those matters with significant updates and new matters since our disclosure in our 2018 Form 10-K and our 2019 First Quarter Form 10-Q are reported herein. In addition to the matters described below and in our 2018 Form 10-K and our 2019 First Quarter Form 10-Q, in the ordinary course of business, we are routinely named as defendants in, or as parties to, various legal actions and proceedings relating to activities of our current and/or former operations. These legal actions and proceedings may include claims for substantial or indeterminate compensatory or punitive damages, or for injunctive relief. In the ordinary course of business, we also are subject to governmental and regulatory examinations, information-gathering requests, investigations and proceedings (both formal and informal), certain of which may result in adverse judgments, settlements, fines, penalties, injunctions or other relief. In connection with formal and informal inquiries by these regulators, we receive numerous requests, subpoenas and orders seeking documents, testimony and other information in connection with various aspects of our regulated activities. Due to the inherent unpredictability of legal matters, including litigation, governmental and regulatory matters, particularly where the damages sought are substantial or indeterminate or when the proceedings or investigations are in the early stages, we cannot determine with any degree of certainty the timing or ultimate resolution of such matters or the eventual loss, fines, penalties or business impact, if any, that may result. We establish reserves for litigation, governmental and regulatory matters when those matters present loss contingencies that are both probable and can be reasonably estimated. Once established, reserves are adjusted from time to time, as appropriate, in light of additional information. The actual costs of resolving litigation and regulatory matters, however, may be substantially higher than the amounts reserved for those matters. During both the three and six months ended June 30, 2019, we recorded expense related to legal matters (excluding attorney's fees) of $3 million compared with expense of $16 million and $510 million during the three and six months ended June 30, 2018, respectively. The expense in the 2018 periods included expense related to a mortgage securitization matter that was settled in October 2018. See Note 28, "Litigation and Regulatory Matters," in our 2018 Form 10-K for additional discussion. For the legal matters disclosed below, including litigation and governmental and regulatory matters, as well as for the legal matters disclosed in Note 28, "Litigation and Regulatory Matters," in our 2018 Form 10-K and in Note 20, "Litigation and Regulatory Matters," in our 2019 First Quarter Form 10-Q, as to which a loss in excess of accrued liability is reasonably possible in future periods and for which there is sufficient currently available information on the basis of which management believes it can make a reliable estimate, we believe a reasonable estimate could be as much as $375 million for HUSI. The legal matters underlying this estimate of possible loss will change from time to time and actual results may differ significantly from this current estimate. In addition, based on the facts currently known for each of the ongoing investigations disclosed in Note 28, "Litigation and Regulatory Matters," in our 2018 Form 10-K and in Note 20, "Litigation and Regulatory Matters," in our 2019 First Quarter Form 10-Q, it is not practicable at this time for us to determine the terms on which these ongoing investigations will be resolved or the timing of such resolution. As matters progress, it is possible that any fines and/or penalties could be significant. Given the substantial or indeterminate amounts sought in certain of these matters, and the inherent unpredictability of such matters, an adverse outcome in certain of these matters could have a material adverse effect on our consolidated financial statements in any particular quarterly or annual period. DeKalb County, et al. v. HSBC North America Holdings Inc., et al . (N.D. Ga. Case No. 12-CV-03640) In May 2019, the U.S. Court of Appeals for the Eleventh Circuit ("Eleventh Circuit") issued a decision in the City of Miami v. Bank of America Corp. & Wells Fargo & Co. case upon remand from the U.S. Supreme Court. The Eleventh Circuit held that the City of Miami had plausibly alleged damages in the form of lost property tax revenue, but had not adequately pled other forms of damages (increased municipal expenditures). The City of Miami defendants have sought rehearing of that decision before the full panel of the court. County of Cook v. HSBC North America Holdings Inc., et al. (N.D. Ill. Case No. 1:14-cv-2031) In June 2019, Cook County moved for reconsideration of the district court's May 2018 order that, among other things, significantly narrowed the categories of damages available for potential recovery, based on the Eleventh Circuit’s decision in the City of Miami v. Bank of America Corp. & Wells Fargo & Co. case. Credit Default Swap Matters In July 2019, the court granted the motion to dismiss the action filed by TeraExchange, LLC as to certain defendants, including the HSBC defendants. Foreign Exchange ("FX") Matters U.S. Litigation FX Opt Out Litigation In June 2019, plaintiffs filed a second amended complaint. Defendants have moved to dismiss the complaint. Contant In May 2019, the court denied HSBC Bank plc's motion to dismiss for lack of personal jurisdiction. It is possible that additional actions will be initiated against the HSBC entities, including HSBC Bank USA, in relation to their historical foreign exchange activities. Investigations In June 2019, the South African Competition Tribunal issued a decision requiring the Competition Commission of South Africa to revise its complaint. The South African Competition Tribunal also dismissed HSBC Bank USA from the complaint, but permitted the Competition Commission of South Africa to apply for it to be re-joined, albeit on the basis that HSBC Bank USA cannot be fined or ordered to pay damages and only a declaratory order can be issued against it. Several financial institutions named in the complaint, including HSBC Bank USA, have appealed part of the decision to the Competition Appeal Court of South Africa, and the Competition Commission of South Africa has cross-appealed. Madoff Litigation In April 2019, the Second Circuit granted the non-U.S. HSBC defendants' motion to stay the case pending before the U.S. Bankruptcy Court to allow for the filing of a petition to the U.S. Supreme Court to seek review of the Second Circuit's decision reversing the dismissal of claims against them. Benchmark Rate Litigation ICE Libor: Plaintiffs filed an amended complaint in July 2019. Mortgage Securitization Trust Litigation In May 2019, the Virginia Supreme Court overturned the lower court's dismissal of the Fir Tree case on procedural grounds. HSBC Bank USA moved for reconsideration of the decision. Anti-Terrorism Act Cases Timothy O'Sullivan, et al. v. Deutsche Bank AG, et al. In April 2019, plaintiffs filed a motion for leave to amend the complaint as permitted by the court’s order to dismiss. Ryan Bowman et al. v. HSBC Holdings plc, et al. The action has been stayed. Rigoberto Vasquez and Eva Garcia et al v. Hong Kong and Shanghai Banking Corporation Ltd., HSBC Bank USA, N.A., et al. In May 2019, the U.S. District Court for the Southern District of New York granted HSBC Bank USA's motion and dismissed it from the case. Telephone Consumer Protection Act Litigation In June 2019, the U.S. District Court for the Central District of California granted preliminary approval of the settlement. The final approval hearing is scheduled for December 2019. Frank Ortega v. HSBC Bank USA, National Association In June 2019, plaintiff filed a purported class action in California Superior Court in Los Angeles County based upon an October 2018 data breach experienced by HSBC Bank USA. The purported class members are HSBC Bank USA customers from October 4, 2018 to October 14, 2018 whose personal information allegedly was compromised. Plaintiff alleges he suffered actual harm in the form of fraudulent charges on his account, as well as continuing harm resulting from the compromise of his and other purported class members' personal data. The complaint asserts claims for breach of contract, breach of the covenant of good faith and fair dealing, violation of the California Business and Professions Code 17200, negligence, and violation of the Consumers Legal Remedies Act 1750, and seeks unspecified monetary damages and injunctive relief. The case is at a very early stage. Other Regulatory and Law Enforcement Investigations HSBC Bank USA is being investigated by the Commodity Futures Trading Commission ("CFTC") for certain swap dealer trade reporting and other regulatory and trading issues related to prior periods. We are cooperating with the CFTC.

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements The following new accounting pronouncements were adopted effective January 1, 2019: • Leases In February 2016, the Financial Accounting Standards Board ("FASB") issued an Accounting Standards Update ("ASU") which requires a lessee to recognize a lease liability and a ROU asset on its balance sheet for all leases, including operating leases. Lease classification is still performed, with any lease classified as a finance lease reported as a financing transaction. The ASU does not substantially change lessor accounting. Additionally, the ASU makes several other targeted amendments including a) revising the definition of lease payments to include fixed payments by the lessee to cover lessor costs related to ownership of the underlying asset such as for property taxes or insurance; b) requiring seller-lessees in a sale-leaseback transaction to recognize the entire gain from the sale of the underlying asset at the time of sale rather than over the leaseback term; and c) expanding disclosures to provide quantitative and qualitative information about lease transactions. The adoption of this guidance resulted in a gross-up of our balance sheet of approximately $780 million as a result of recognizing lease liabilities and corresponding ROU assets for operating leases upon adoption as of January 1, 2019. In accordance with the new guidance, we elected the short-term lease exemption for all leases with a term of 12 months or less and, therefore, do not recognize ROU assets or lease liabilities for short-term leases. The adoption of this guidance also required a cumulative effect adjustment to the consolidated balance sheet to recognize the previously deferred gain on the sale and leaseback of our 452 Fifth Avenue property, which resulted in an increase in retained earnings of $27 million , after tax, as of January 1, 2019. The adoption of this guidance did not result in material changes to the recognition of operating lease expense. See Note 8, "Leases," for the new disclosure required by this standard. • Premium Amortization on Purchased Callable Debt Securities In March 2017, the FASB issued an ASU that shortens the premium amortization period for purchased non-contingently callable debt securities by requiring the premium to be amortized to the earliest call date, rather than the contractual maturity date. After the earliest call date, if the call option is not exercised, the effective yield will be reset using the payment terms of the debt security. The new guidance does not change the discount amortization period for purchased debt securities. The discount continues to be amortized to the contractual maturity date. The adoption of this guidance did not have a material impact on our consolidated financial statements. • Derivatives and Hedging - Targeted Improvements to Accounting for Hedging Activities In August 2017, the FASB issued an ASU amending its hedge accounting guidance to expand an entity's ability to hedge nonfinancial and financial risk components, reduce complexity in fair value hedges of interest rate risk and ease the requirements for effectiveness testing and hedge documentation. The ASU eliminates the requirement to separately measure and report hedge ineffectiveness and generally requires the entire change in the fair value of a hedging instrument to be presented in the same income statement line as the hedged item. The ASU also requires expanded disclosures. The adoption of this guidance did not have a material impact on our consolidated financial statements. See Note 9, "Derivative Financial Instruments," for additional information, including the new disclosure required by this standard. The following are accounting pronouncements which will be adopted in future periods: • Financial Instruments - Credit Impairment In June 2016, the FASB issued an ASU that will significantly change measurement of credit losses. The ASU requires recognition of lifetime expected credit losses for loans (including TDR loans), held-to-maturity and AFS debt securities, off-balance sheet credit exposures and certain other financial assets reported at amortized cost. Modeling and economic forecasting requirements of the ASU are new and extensive, and the ASU's requirements differ significantly from the IFRS credit loss reporting that we implemented in 2018 for reporting to HSBC. We are currently in the process of completing these requirements. The ASU is effective for all annual and interim periods beginning no later than January 1, 2020 and is required to be applied by recording a cumulative effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. Based on our present expectations of credit performance by our relevant financial assets, we do not expect our one-time ASU adoption adjustment to be material. • Goodwill Impairment Testing In January 2017, the FASB issued an ASU that simplifies the accounting for goodwill impairment by removing step two of the goodwill impairment test. Under step two, an entity was required to determine the fair value of individual assets and liabilities of a reporting unit (including unrecognized assets and liabilities) using the procedure for determining fair values in a business combination. Under the new guidance, goodwill impairment will now be measured at the amount by which a reporting unit's carrying amount, including those with a zero or negative carrying amount, exceeds its fair value. Any resulting impairment is limited to the carrying amount of goodwill. An entity must also disclose the amount of goodwill allocated to each reporting unit with a zero or negative carrying amount. The ASU is effective for all annual and interim periods beginning January 1, 2020 and is required to be applied prospectively with early adoption permitted. The adoption of this guidance is not expected to have a material impact on the results of our goodwill impairment testing or our consolidated financial statements. • Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued an ASU that eliminates, amends and adds certain disclosure requirements for fair value measurements. The ASU is effective for all annual and interim periods beginning January 1, 2020, with early adoption permitted. We elected to early adopt the new guidance related to the eliminated and amended disclosure requirements in 2018. While adoption of the remaining guidance will result in changes to our existing disclosures, it will not have any additional impact on our consolidated financial statements. There have been no additional accounting pronouncements issued that are expected to have or could have a material impact on our consolidated financial statements.

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements (Policies)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Hierarchy	Fair Value Hierarchy The Fair Value Framework establishes a three-tiered fair value hierarchy as follows: Level 1 quoted market price - Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 valuation technique using observable inputs - Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are inactive, and measurements determined using valuation models where all significant inputs are observable, such as interest rates and yield curves that are observable at commonly quoted intervals. Level 3 valuation technique with significant unobservable inputs - Level 3 inputs are unobservable inputs for the asset or liability and include situations where fair values are measured using valuation techniques based on one or more significant unobservable inputs. Classification within the fair value hierarchy is based on whether the lowest hierarchical level input that is significant to the fair value measurement is observable. As such, the classification within the fair value hierarchy is dynamic and can be transferred to other hierarchy levels in each reporting period.

Trading Assets and Liabilities

Trading Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2019
Trading Assets And Liabilities [Abstract]
Trading Assets and Liabilities	Trading assets and liabilities consisted of the following: June 30, 2019 December 31, 2018 (in millions) Trading assets: U.S. Treasury $ 10,620 $ 5,368 U.S. Government agency issued or guaranteed 19 111 U.S. Government sponsored enterprises 59 41 Asset-backed securities 192 208 Corporate and foreign bonds 12,925 10,562 Equity securities 2,747 751 Precious metals 3,895 1,889 Derivatives, net 3,045 3,048 Total trading assets $ 33,502 $ 21,978 Trading liabilities: Securities sold, not yet purchased $ 834 $ 738 Payables for precious metals 106 215 Derivatives, net 3,086 2,690 Total trading liabilities $ 4,026 $ 3,643

Securities (Tables)

Securities (Tables)	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Amortized Cost and Fair Value of the Securities Available-for-Sale and Held-to-Maturity	Our securities available-for-sale and securities held-to-maturity portfolios consisted of the following: June 30, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) Securities available-for-sale: U.S. Treasury $ 16,942 $ 148 $ (264 ) $ 16,826 U.S. Government sponsored enterprises: Mortgage-backed securities 4,777 76 (26 ) 4,827 Collateralized mortgage obligations 684 2 (5 ) 681 Direct agency obligations 2,751 29 (1 ) 2,779 U.S. Government agency issued or guaranteed: Mortgage-backed securities 7,834 24 (61 ) 7,797 Collateralized mortgage obligations 964 10 (7 ) 967 Direct agency obligations 252 2 (1 ) 253 Asset-backed securities collateralized by: Home equity 39 — (3 ) 36 Other 108 5 — 113 Foreign debt securities (1) 2,971 4 — 2,975 Total available-for-sale securities $ 37,322 $ 300 $ (368 ) $ 37,254 Securities held-to-maturity: U.S. Government sponsored enterprises: Mortgage-backed securities $ 1,843 $ 15 $ (3 ) $ 1,855 Collateralized mortgage obligations 1,718 46 (7 ) 1,757 U.S. Government agency issued or guaranteed: Mortgage-backed securities 2,179 6 (2 ) 2,183 Collateralized mortgage obligations 8,174 67 (39 ) 8,202 Obligations of U.S. states and political subdivisions 11 1 — 12 Asset-backed securities collateralized by residential mortgages 2 — — 2 Total held-to-maturity securities $ 13,927 $ 135 $ (51 ) $ 14,011 December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) Securities available-for-sale: U.S. Treasury $ 13,549 $ 106 $ (365 ) $ 13,290 U.S. Government sponsored enterprises: Mortgage-backed securities 5,541 6 (154 ) 5,393 Collateralized mortgage obligations 686 1 (35 ) 652 Direct agency obligations 2,831 37 (2 ) 2,866 U.S. Government agency issued or guaranteed: Mortgage-backed securities 4,442 1 (171 ) 4,272 Collateralized mortgage obligations 1,140 9 (29 ) 1,120 Direct agency obligations 295 9 — 304 Asset-backed securities collateralized by: Home equity 44 — (2 ) 42 Other 102 5 — 107 Foreign debt securities (1) 3,330 3 — 3,333 Total available-for-sale securities $ 31,960 $ 177 $ (758 ) $ 31,379 Securities held-to-maturity: U.S. Government sponsored enterprises: Mortgage-backed securities $ 1,812 $ 1 $ (34 ) $ 1,779 Collateralized mortgage obligations 1,878 34 (26 ) 1,886 U.S. Government agency issued or guaranteed: Mortgage-backed securities 2,104 2 (63 ) 2,043 Collateralized mortgage obligations 8,863 35 (176 ) 8,722 Obligations of U.S. states and political subdivisions 11 — — 11 Asset-backed securities collateralized by residential mortgages 2 — — 2 Total held-to-maturity securities $ 14,670 $ 72 $ (299 ) $ 14,443 (1) Foreign debt securities represent public sector entity, bank or corporate debt.
Gross Unrealized Losses and Related Fair Value	The following table summarizes gross unrealized losses and related fair values at June 30, 2019 and December 31, 2018 classified as to the length of time the losses have existed: One Year or Less Greater Than One Year June 30, 2019 Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment (dollars are in millions) Securities available-for-sale: U.S. Treasury 17 $ (31 ) $ 3,652 32 $ (233 ) $ 6,030 U.S. Government sponsored enterprises 1 — 252 122 (32 ) 2,678 U.S. Government agency issued or guaranteed 2 (6 ) 177 59 (63 ) 4,093 Asset-backed securities — — — 5 (3 ) 36 Foreign debt securities 18 — 1,440 — — — Securities available-for-sale 38 $ (37 ) $ 5,521 218 $ (331 ) $ 12,837 Securities held-to-maturity: U.S. Government sponsored enterprises 12 $ — $ 3 301 $ (10 ) $ 1,210 U.S. Government agency issued or guaranteed 32 — 187 386 (41 ) 4,769 Obligations of U.S. states and political subdivisions — — — 1 — — Securities held-to-maturity 44 $ — $ 190 688 $ (51 ) $ 5,979 One Year or Less Greater Than One Year December 31, 2018 Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment Number of Securities Gross Unrealized Losses Aggregate Fair Value of Investment (dollars are in millions) Securities available-for-sale: U.S. Treasury 8 $ (12 ) $ 1,013 41 $ (353 ) $ 8,828 U.S. Government sponsored enterprises 55 (6 ) 538 159 (185 ) 3,698 U.S. Government agency issued or guaranteed 8 (2 ) 106 72 (198 ) 4,825 Asset-backed securities 1 — — 4 (2 ) 42 Foreign debt securities 16 — 1,724 — — — Securities available-for-sale 88 $ (20 ) $ 3,381 276 $ (738 ) $ 17,393 Securities held-to-maturity: U.S. Government sponsored enterprises 103 $ (8 ) $ 684 511 $ (52 ) $ 1,739 U.S. Government agency issued or guaranteed 111 (14 ) 769 491 (225 ) 7,372 Obligations of U.S. states and political subdivisions 1 — — 1 — — Securities held-to-maturity 215 $ (22 ) $ 1,453 1,003 $ (277 ) $ 9,111
Realized Gains and Losses on Investment Securities Transactions Attributable to Available-for-Sale Securities	The following table summarizes realized gains and losses on investment securities transactions attributable to available-for-sale securities: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Gross realized gains $ 27 $ 21 $ 43 $ 30 Gross realized losses (4 ) (11 ) (13 ) (15 ) Net realized gains $ 23 $ 10 $ 30 $ 15
Distribution of Maturities of Debt Securities with the Approximate Yield of the Portfolio	The table below also reflects the distribution of maturities of debt securities held at June 30, 2019 , together with the approximate yield of the portfolio. The yields shown are calculated by dividing annualized interest income, including the accretion of discounts and the amortization of premiums, by the amortized cost of securities outstanding at June 30, 2019 . Within One Year After One But Within Five Years After Five But Within Ten Years After Ten Years Amount Yield Amount Yield Amount Yield Amount Yield (dollars are in millions) Available-for-sale: U.S. Treasury $ 199 2.22 % $ 7,760 1.81 % $ 5,967 2.05 % $ 3,016 2.80 % U.S. Government sponsored enterprises 1,047 2.99 1,168 2.83 2,218 2.74 3,779 3.00 U.S. Government agency issued or guaranteed — — 81 2.21 1 4.33 8,968 2.72 Asset-backed securities — — — — 58 5.21 89 3.90 Foreign debt securities 1,552 .00 1,419 2.56 — — — — Total amortized cost $ 2,798 1.27 % $ 10,428 2.03 % $ 8,244 2.26 % $ 15,852 2.81 % Total fair value $ 2,801 $ 10,445 $ 8,191 $ 15,817 Held-to-maturity: U.S. Government sponsored enterprises $ 50 2.22 % $ 376 2.72 % $ 269 2.45 % $ 2,866 3.04 % U.S. Government agency issued or guaranteed — — 13 3.94 22 3.69 10,318 2.68 Obligations of U.S. states and political subdivisions 1 4.75 5 3.46 5 4.20 — — Asset-backed securities — — — — — — 2 7.83 Total amortized cost $ 51 2.27 % $ 394 2.77 % $ 296 2.57 % $ 13,186 2.76 % Total fair value $ 51 $ 399 $ 298 $ 13,263
Equity Securities Not Classified as Trading	Equity securities that are not classified as trading and are included in other assets consisted of the following: June 30, 2019 December 31, 2018 (in millions) Equity securities carried at fair value $ 302 $ 278 Equity securities without readily determinable fair values 9 7

Loans (Tables)

Loans (Tables)	6 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Components of Loans	Loans consisted of the following: June 30, 2019 December 31, 2018 (in millions) Commercial loans: Real estate, including construction $ 11,704 $ 11,344 Business and corporate banking 14,310 13,066 Global banking (1) 20,896 20,167 Other commercial (2) 5,835 4,765 Total commercial 52,745 49,342 Consumer loans: Residential mortgages 17,421 17,383 Home equity mortgages 911 982 Credit cards 1,129 1,019 Other consumer 272 252 Total consumer 19,733 19,636 Total loans $ 72,478 $ 68,978 (1) Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers. (2) Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018 , respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.
Summary of Past Due Status of Loans	The following table summarizes the past due status of our loans, excluding loans held for sale, at June 30, 2019 and December 31, 2018 . The aging of past due amounts is determined based on the contractual delinquency status of payments under the loan. An account is generally considered to be contractually delinquent when payments have not been made in accordance with the loan terms. Delinquency status is affected by customer account management policies and practices such as re-age, which results in the re-setting of the contractual delinquency status to current. Past Due Total Past Due 30 Days or More At June 30, 2019 30 - 89 Days 90+ Days Current (1) Total Loans (in millions) Commercial loans: Real estate, including construction $ 10 $ 1 $ 11 $ 11,693 $ 11,704 Business and corporate banking 10 19 29 14,281 14,310 Global banking — — — 20,896 20,896 Other commercial — — — 5,835 5,835 Total commercial 20 20 40 52,705 52,745 Consumer loans: Residential mortgages 341 257 598 16,823 17,421 Home equity mortgages 12 25 37 874 911 Credit cards 16 18 34 1,095 1,129 Other consumer 6 4 10 262 272 Total consumer 375 304 679 19,054 19,733 Total loans $ 395 $ 324 $ 719 $ 71,759 $ 72,478 Past Due Total Past Due 30 Days or More At December 31, 2018 30 - 89 Days 90+ Days Current (1) Total Loans (in millions) Commercial loans: Real estate, including construction $ 76 $ 3 $ 79 $ 11,265 $ 11,344 Business and corporate banking 79 38 117 12,949 13,066 Global banking — — — 20,167 20,167 Other commercial 15 — 15 4,750 4,765 Total commercial 170 41 211 49,131 49,342 Consumer loans: Residential mortgages 469 254 723 16,660 17,383 Home equity mortgages 14 27 41 941 982 Credit cards 13 14 27 992 1,019 Other consumer 5 5 10 242 252 Total consumer 501 300 801 18,835 19,636 Total loans $ 671 $ 341 $ 1,012 $ 67,966 $ 68,978 (1) Loans less than 30 days past due are presented as current.
Summary of Nonaccrual Loans and Accruing Receivables 90 Days or More Delinquent	Nonaccrual loans, including nonaccrual loans held for sale, and accruing loans 90 days or more delinquent consisted of the following: June 30, 2019 December 31, 2018 (in millions) Nonaccrual loans: Commercial: Real estate, including construction $ 7 $ 7 Business and corporate banking 90 70 Global banking 53 65 Other commercial — 1 Commercial nonaccrual loans held for sale 22 — Total commercial 172 143 Consumer: Residential mortgages (1)(2)(3) 370 341 Home equity mortgages (1)(2) 48 55 Consumer nonaccrual loans held for sale 1 1 Total consumer 419 397 Total nonaccruing loans 591 540 Accruing loans contractually past due 90 days or more: Commercial: Business and corporate banking 1 1 Total commercial 1 1 Consumer: Credit cards 18 14 Other consumer 4 6 Total consumer 22 20 Total accruing loans contractually past due 90 days or more 23 21 Total nonperforming loans $ 614 $ 561 (1) At June 30, 2019 and December 31, 2018 , nonaccrual consumer mortgage loans held for investment include $267 million and $289 million , respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell. (2) Nonaccrual consumer mortgage loans held for investment include all loans which are 90 or more days contractually delinquent as well as loans discharged under Chapter 7 bankruptcy and not re-affirmed and second lien loans where the first lien loan that we own or service is 90 or more days contractually delinquent. (3) Nonaccrual consumer mortgage loans for all periods does not include guaranteed loans purchased from the Government National Mortgage Association. Repayment of these loans is predominantly insured by the Federal Housing Administration and as such, these loans have different risk characteristics from the rest of our consumer loan portfolio.
Schedule of Additional Information on Nonaccrual Loans	The following table provides additional information on our nonaccrual loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest income that would have been recorded if the nonaccrual loans had been current in accordance with contractual terms during the period $ 7 $ 13 $ 16 $ 27 Interest income that was recorded on nonaccrual loans and included in interest income during the period 3 6 6 15
Summary of Receivables which were Modified and as a Result Became Classified as TDR Loans	The following table presents information about loans which were modified during the three and six months ended June 30, 2019 and 2018 and as a result of this action became classified as TDR Loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Residential mortgages $ — $ 12 $ 1 $ 17 Home equity mortgages — 1 — 3 Credit cards 1 1 2 2 Total consumer $ 1 $ 14 $ 3 $ 22
Summary of TDR and Related Credit Loss Reserves for TDR Loans	The following table presents information about our TDR Loans and the related allowance for credit losses for TDR Loans: June 30, 2019 December 31, 2018 Carrying Value Unpaid Principal Balance Carrying Value Unpaid Principal Balance (in millions) TDR Loans: (1)(2) Commercial loans: Business and corporate banking $ 59 $ 74 $ 68 $ 86 Global banking 84 92 113 119 Total commercial (3) 143 166 181 205 Consumer loans: Residential mortgages (4) 608 694 640 730 Home equity mortgages (4) 33 62 35 65 Credit cards 4 4 3 4 Total consumer 645 760 678 799 Total TDR Loans (5) $ 788 $ 926 $ 859 $ 1,004 Allowance for credit losses for TDR Loans: (6) Commercial loans: Business and corporate banking $ 12 $ 12 Global banking — — Total commercial 12 12 Consumer loans: Residential mortgages 3 3 Home equity mortgages — 1 Credit cards 1 1 Total consumer 4 5 Total allowance for credit losses for TDR Loans $ 16 $ 17 (1) TDR Loans are considered to be impaired loans. For commercial loans, impaired loans include other loans in addition to TDR Loans which totaled $63 million and $54 million at June 30, 2019 and December 31, 2018 , respectively. (2) The carrying value of TDR Loans includes basis adjustments on the loans, such as partial charge-offs. (3) Additional commitments to lend to commercial borrowers whose loans have been modified in TDR Loans totaled $226 million and $151 million at June 30, 2019 and December 31, 2018 , respectively. (4) At June 30, 2019 and December 31, 2018 , the carrying value of consumer mortgage TDR Loans held for investment includes $584 million and $615 million , respectively, of loans that are recorded at the lower of amortized cost or fair value of the collateral less cost to sell. (5) At June 30, 2019 and December 31, 2018 , the carrying value of TDR Loans includes $256 million and $286 million , respectively, of loans which are classified as nonaccrual. (6) Included in the allowance for credit losses.
Troubled Debt Restructuring Additional Information	The following table presents information about average TDR Loans and interest income recognized on TDR Loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Average balance of TDR Loans: Commercial loans: Business and corporate banking $ 65 $ 137 $ 66 $ 156 Global banking 82 110 92 132 Total commercial 147 247 158 288 Consumer loans: Residential mortgages 615 664 621 670 Home equity mortgages 33 35 34 34 Credit cards 4 4 4 4 Total consumer 652 703 659 708 Total average balance of TDR Loans $ 799 $ 950 $ 817 $ 996 Interest income recognized on TDR Loans: Commercial loans: Business and corporate banking $ 1 $ — $ 2 $ 4 Global banking — 1 1 2 Total commercial 1 1 3 6 Consumer loans: Residential mortgages 6 7 13 14 Home equity mortgages 1 1 1 1 Total consumer 7 8 14 15 Total interest income recognized on TDR Loans $ 8 $ 9 $ 17 $ 21
Loans Classified as TDR Loans	The following table presents consumer loans which were classified as TDR Loans during the previous 12 months which subsequently became 60 days or greater contractually delinquent during the three and six months ended June 30, 2019 and 2018 : Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Consumer loans: Residential mortgages $ 1 $ — $ 3 $ 2 Home equity mortgages — 1 — 2 Total consumer $ 1 $ 1 $ 3 $ 4
Impaired Commercial Loans Considered as TDR Loans	The following table presents information about impaired commercial loans and the related impairment reserve: Amount with Impairment Reserves (1) Amount without Impairment Reserves (1) Total Impaired Commercial Loans (1)(2) Impairment Reserve Unpaid Principal Balance (in millions) At June 30, 2019 Real estate, including construction $ 3 $ 1 $ 4 $ 2 $ 4 Business and corporate banking 46 55 101 21 110 Global banking — 101 101 — 111 Total commercial $ 49 $ 157 $ 206 $ 23 $ 225 At December 31, 2018 Real estate, including construction $ 3 $ 3 $ 6 $ 1 $ 6 Business and corporate banking 58 37 95 18 109 Global banking — 133 133 — 140 Other commercial — 1 1 — 1 Total commercial $ 61 $ 174 $ 235 $ 19 $ 256 (1) Reflects the carrying value of impaired commercial loans and includes basis adjustments on the loans, such as partial charge-offs. (2) Includes impaired commercial loans that are also considered TDR Loans which totaled $143 million and $181 million at June 30, 2019 and December 31, 2018 , respectively.
Average Balance and Interest Income Recognized on Impaired Commercial Loans	The following table presents information about average impaired commercial loans and interest income recognized on impaired commercial loans: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Average balance of impaired commercial loans: Real estate, including construction $ 4 $ 12 $ 5 $ 11 Business and corporate banking 105 272 101 264 Global banking 100 248 111 311 Total average balance of impaired commercial loans $ 209 $ 532 $ 217 $ 586 Interest income recognized on impaired commercial loans: Business and corporate banking $ 2 $ 1 $ 3 $ 6 Global banking — 1 1 2 Total interest income recognized on impaired commercial loans $ 2 $ 2 $ 4 $ 8
Summary of Criticized Assets for Commercial Loans	The following table summarizes criticized commercial loans: Special Mention Substandard Doubtful Total (in millions) At June 30, 2019 Real estate, including construction $ 784 $ 151 $ 1 $ 936 Business and corporate banking 282 441 27 750 Global banking 243 276 — 519 Total commercial $ 1,309 $ 868 $ 28 $ 2,205 At December 31, 2018 Real estate, including construction $ 452 $ 93 $ 4 $ 549 Business and corporate banking 193 314 15 522 Global banking 262 277 — 539 Other commercial — 1 — 1 Total commercial $ 907 $ 685 $ 19 $ 1,611
Status of Commercial Loan Portfolio	The following table summarizes the status of our commercial loan portfolio, excluding loans held for sale: Performing Loans Nonaccrual Loans Accruing Loans Contractually Past Due 90 days or More Total (in millions) At June 30, 2019 Real estate, including construction $ 11,697 $ 7 $ — $ 11,704 Business and corporate banking 14,219 90 1 14,310 Global banking 20,843 53 — 20,896 Other commercial 5,835 — — 5,835 Total commercial $ 52,594 $ 150 $ 1 $ 52,745 At December 31, 2018 Real estate, including construction $ 11,337 $ 7 $ — $ 11,344 Business and corporate banking 12,995 70 1 13,066 Global banking 20,102 65 — 20,167 Other commercial 4,764 1 — 4,765 Total commercial $ 49,198 $ 143 $ 1 $ 49,342
Credit Risk Profile of Commercial Loan	The following table shows the credit risk profile of our commercial loan portfolio: Investment Grade (1) Non-Investment Grade Total (in millions) At June 30, 2019 Real estate, including construction $ 6,807 $ 4,897 $ 11,704 Business and corporate banking 5,969 8,341 14,310 Global banking 14,860 6,036 20,896 Other commercial 5,158 677 5,835 Total commercial $ 32,794 $ 19,951 $ 52,745 At December 31, 2018 Real estate, including construction $ 6,769 $ 4,575 $ 11,344 Business and corporate banking 5,674 7,392 13,066 Global banking 14,764 5,403 20,167 Other commercial 3,990 775 4,765 Total commercial $ 31,197 $ 18,145 $ 49,342 (1) Investment grade includes commercial loans with credit ratings of at least BBB- or above or the equivalent based on our internal credit rating system.
Delinquency Ratio for Consumer Loan	The following table summarizes dollars of two-months-and-over contractual delinquency and as a percent of total loans and loans held for sale ("delinquency ratio") for our consumer loan portfolio: June 30, 2019 December 31, 2018 Delinquent Loans Delinquency Ratio Delinquent Loans Delinquency Ratio (dollars are in millions) Residential mortgages (1)(2) $ 319 1.83 % $ 347 1.99 % Home equity mortgages (1)(2) 27 2.96 30 3.05 Credit cards 25 2.21 20 1.96 Other consumer 6 2.21 8 2.62 Total consumer $ 377 1.91 % $ 405 2.05 % (1) At June 30, 2019 and December 31, 2018 , consumer mortgage loan delinquency includes $239 million and $254 million , respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell, including $1 million and $1 million , respectively, relating to loans held for sale. (2) At June 30, 2019 and December 31, 2018 , consumer mortgage loans and loans held for sale include $146 million and $125 million , respectively, of loans that were in the process of foreclosure.
Status of Consumer Loan Portfolio	The following table summarizes the status of our consumer loan portfolio, excluding loans held for sale: Performing Loans Nonaccrual Loans Accruing Loans Contractually Past Due 90 days or More Total (in millions) At June 30, 2019 Residential mortgages $ 17,051 $ 370 $ — $ 17,421 Home equity mortgages 863 48 — 911 Credit cards 1,111 — 18 1,129 Other consumer 268 — 4 272 Total consumer $ 19,293 $ 418 $ 22 $ 19,733 At December 31, 2018 Residential mortgages $ 17,042 $ 341 $ — $ 17,383 Home equity mortgages 927 55 — 982 Credit cards 1,005 — 14 1,019 Other consumer 246 — 6 252 Total consumer $ 19,220 $ 396 $ 20 $ 19,636

Allowance for Credit Losses (Ta

Allowance for Credit Losses (Tables)	6 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Summary of Changes in the Allowance for Credit Losses and the Related Loan Balance by Product	The following table summarizes the changes in the allowance for credit losses by product and the related loan balance by product during the three and six months ended June 30, 2019 and 2018 : Commercial Consumer Real Estate, including Construction Business Global Other Residential Home Credit Other Total (in millions) Three Months Ended June 30, 2019 Allowance for credit losses – beginning of period $ 119 $ 239 $ 122 $ 15 $ 10 $ 8 $ 63 $ 7 $ 583 Provision charged (credited) to income 30 13 (9 ) (6 ) 1 (1 ) 19 (1 ) 46 Charge-offs — (2 ) (3 ) — (3 ) (1 ) (12 ) (2 ) (23 ) Recoveries — 1 — — 3 1 1 1 7 Net (charge-offs) recoveries — (1 ) (3 ) — — — (11 ) (1 ) (16 ) Allowance for credit losses – end of period $ 149 $ 251 $ 110 $ 9 $ 11 $ 7 $ 71 $ 5 $ 613 Three Months Ended June 30, 2018 Allowance for credit losses – beginning of period $ 92 $ 207 $ 211 $ 19 $ 18 $ 10 $ 38 $ 4 $ 599 Provision charged (credited) to income (4 ) (27 ) (25 ) — (4 ) — 13 2 (45 ) Charge-offs — (6 ) (32 ) — (1 ) (2 ) (7 ) (2 ) (50 ) Recoveries — 22 — — 2 1 1 1 27 Net (charge-offs) recoveries — 16 (32 ) — 1 (1 ) (6 ) (1 ) (23 ) Allowance for credit losses – end of period $ 88 $ 196 $ 154 $ 19 $ 15 $ 9 $ 45 $ 5 $ 531 Six Months Ended June 30, 2019 Allowance for credit losses – beginning of period $ 116 $ 219 $ 108 $ 15 $ 13 $ 7 $ 58 $ 5 $ 541 Provision charged (credited) to income 33 35 5 (6 ) — — 35 2 104 Charge-offs — (4 ) (3 ) — (7 ) (2 ) (25 ) (3 ) (44 ) Recoveries — 1 — — 5 2 3 1 12 Net (charge-offs) recoveries — (3 ) (3 ) — (2 ) — (22 ) (2 ) (32 ) Allowance for credit losses – end of period $ 149 $ 251 $ 110 $ 9 $ 11 $ 7 $ 71 $ 5 $ 613 Ending balance: collectively evaluated for impairment $ 147 $ 230 $ 110 $ 9 $ 8 $ 7 $ 70 $ 5 $ 586 Ending balance: individually evaluated for impairment 2 21 — — 3 — 1 — 27 Total allowance for credit losses $ 149 $ 251 $ 110 $ 9 $ 11 $ 7 $ 71 $ 5 $ 613 Loans: Collectively evaluated for impairment (1) $ 11,700 $ 14,209 $ 20,795 $ 5,835 $ 16,559 $ 854 $ 1,125 $ 272 $ 71,349 Individually evaluated for impairment (2) 4 101 101 — 53 4 4 — 267 Loans carried at lower of amortized cost or fair value less cost to sell — — — — 809 53 — — 862 Total loans $ 11,704 $ 14,310 $ 20,896 $ 5,835 $ 17,421 $ 911 $ 1,129 $ 272 $ 72,478 Commercial Consumer Real Estate, including Construction Business Global Other Residential Home Credit Other Total (in millions) Six Months Ended June 30, 2018 Allowance for credit losses – beginning of period $ 82 $ 244 $ 264 $ 18 $ 25 $ 11 $ 32 $ 5 $ 681 Provision charged (credited) to income 6 (61 ) (74 ) 1 (14 ) (1 ) 25 2 (116 ) Charge-offs — (31 ) (37 ) — (1 ) (4 ) (15 ) (3 ) (91 ) Recoveries — 44 1 — 5 3 3 1 57 Net (charge-offs) recoveries — 13 (36 ) — 4 (1 ) (12 ) (2 ) (34 ) Allowance for credit losses – end of period $ 88 $ 196 $ 154 $ 19 $ 15 $ 9 $ 45 $ 5 $ 531 Ending balance: collectively evaluated for impairment $ 87 $ 169 $ 139 $ 19 $ 10 $ 8 $ 44 $ 5 $ 481 Ending balance: individually evaluated for impairment 1 27 15 — 5 1 1 — 50 Total allowance for credit losses $ 88 $ 196 $ 154 $ 19 $ 15 $ 9 $ 45 $ 5 $ 531 Loans: Collectively evaluated for impairment (1) $ 11,234 $ 11,852 $ 18,704 $ 4,612 $ 16,397 $ 1,019 $ 837 $ 303 $ 64,958 Individually evaluated for impairment (2) 11 257 173 — 59 3 4 — 507 Loans carried at lower of amortized cost or fair value less cost to sell — — — — 870 64 — — 934 Total loans $ 11,245 $ 12,109 $ 18,877 $ 4,612 $ 17,326 $ 1,086 $ 841 $ 303 $ 66,399 (1) Other commercial includes loans to HSBC affiliates totaling $3,096 million and $1,895 million at June 30, 2019 and 2018 , respectively, for which we do not carry an associated allowance for credit losses. (2) For consumer loans and certain small business loans, these amounts represent TDR Loans for which we evaluate reserves using a discounted cash flow methodology. Each loan is individually identified as a TDR Loan and then grouped together with other TDR Loans with similar characteristics. The discounted cash flow analysis is then applied to these groups of TDR Loans. Loans individually evaluated for impairment exclude TDR Loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell which totaled $584 million and $635 million at June 30, 2019 and 2018 , respectively.

Loans Held for Sale (Tables)

Loans Held for Sale (Tables)	6 Months Ended
	Jun. 30, 2019
Receivables [Abstract]
Loans Held for Sale	Loans held for sale consisted of the following: June 30, 2019 December 31, 2018 (in millions) Commercial loans: Real estate, including construction $ 66 $ 27 Global banking 85 367 Total commercial 151 394 Consumer loans: Residential mortgages 40 65 Other consumer — 53 Total consumer 40 118 Total loans held for sale $ 191 $ 512

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Operating Lease Costs and Supplemental Cash Flow Information	The following table summarizes the components of total operating lease costs, net and provides supplemental cash flow information related to leases: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (in millions) Operating lease cost $ 34 $ 66 Variable lease cost 17 31 Short-term lease cost 2 6 Sublease income (14 ) (28 ) Total operating lease costs, net $ 39 $ 75 Supplemental disclosure of cash flow information: Cash paid for amounts included in the measurement of operating lease liabilities $ 31 $ 62 ROU assets recognized for new operating lease liabilities — 10
Operating Lease ROU Assets and Liabilities	The following table presents information about our operating lease ROU assets and liabilities: June 30, 2019 (dollars are in millions) Operating lease ROU assets (1) $ 735 Operating lease liabilities 786 Weighted-average remaining lease term 7.3 years Weighted-average discount rate 3.2 % (1) Reported net of level lease adjustments and exit cost obligations.
Maturity Analysis of Operating Lease Liabilities	The following table presents a maturity analysis of our operating lease liabilities at June 30, 2019 : Year Ending December 31, (in millions) 2019 $ 56 2020 135 2021 135 2022 131 2023 130 Thereafter 312 Total future operating lease payments 899 Less - imputed interest (113 ) Total operating lease liabilities $ 786
Schedule of Future Minimum Lease Commitments	Future net minimum lease commitments under noncancellable operating lease arrangements at December 31, 2018, which did not include renewals, were as follows: Year Ending December 31, Minimum Lease Payments Minimum Sublease Income Net (in millions) 2019 $ 136 $ (58 ) $ 78 2020 125 (2 ) 123 2021 115 (1 ) 114 2022 103 — 103 2023 91 — 91 Thereafter 182 (1 ) 181 Net minimum lease commitments $ 752 $ (62 ) $ 690

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The following table presents the fair value of derivative contracts by major product type on a gross basis. Gross fair values exclude the effects of both counterparty netting as well as collateral, and therefore are not representative of our exposure. The table below also presents the amounts of counterparty netting and cash collateral that have been offset in the consolidated balance sheet, as well as cash and securities collateral posted and received under enforceable master netting agreements that do not meet the criteria for netting. Derivative assets and liabilities which are not subject to an enforceable master netting agreement, or are subject to a netting agreement where an appropriate legal opinion to determine such agreements are enforceable has not been either sought or obtained, have not been netted in the following table. Where we have received or posted collateral under netting agreements where an appropriate legal opinion to determine such agreements are enforceable has not been either sought or obtained, the related collateral also has not been netted in the following table. June 30, 2019 December 31, 2018 Derivative Assets Derivative Liabilities Derivative Assets Derivative Liabilities (in millions) Derivatives accounted for as fair value hedges (1) OTC-cleared (2) $ — $ — $ 6 $ — Bilateral OTC (2) — 161 — 117 Interest rate contracts — 161 6 117 Derivatives accounted for as cash flow hedges (1) Foreign exchange contracts - bilateral OTC (2) 8 23 11 32 Interest rate contracts - bilateral OTC (2) — 31 — 13 Total derivatives accounted for as hedges 8 215 17 162 Trading derivatives not accounted for as hedges (3) Exchange-traded (2) 98 23 2 45 OTC-cleared (2) 51 18 50 14 Bilateral OTC (2) 11,204 12,504 9,866 10,780 Interest rate contracts 11,353 12,545 9,918 10,839 Exchange-traded (2) 1 28 — 15 Bilateral OTC (2) 13,360 12,993 15,897 15,684 Foreign exchange contracts 13,361 13,021 15,897 15,699 Exchange-traded (2) 16 — — — Bilateral OTC (2) 2,738 2,744 2,034 2,061 Equity contracts 2,754 2,744 2,034 2,061 Exchange-traded (2) 106 136 16 274 Bilateral OTC (2) 1,254 1,255 829 626 Precious metals contracts 1,360 1,391 845 900 OTC-cleared (2) 191 178 125 107 Bilateral OTC (2) 927 1,069 825 831 Credit contracts 1,118 1,247 950 938 Other non-qualifying derivatives not accounted for as hedges (1) Interest rate contracts - bilateral OTC (2) 207 67 133 216 Foreign exchange contracts - bilateral OTC (2) 1 8 13 2 Equity contracts - bilateral OTC (2) 1,022 157 512 805 Credit contracts - bilateral OTC (2) 1 28 6 9 Other contracts - bilateral OTC (2)(4) 5 40 5 40 Total derivatives 31,190 31,463 30,330 31,671 Less: Gross amounts of receivable / payable subject to enforceable master netting agreements (5)(7) 24,555 24,555 25,172 25,172 Less: Gross amounts of cash collateral received / posted subject to enforceable master netting agreements (6)(7) 3,439 3,627 2,020 3,675 Net amounts of derivative assets / liabilities presented in the balance sheet 3,196 3,281 3,138 2,824 Less: Gross amounts of financial instrument collateral received / posted subject to enforceable master netting agreements but not offset in the consolidated balance sheet 789 1,572 832 568 Net amounts of derivative assets / liabilities $ 2,407 $ 1,709 $ 2,306 $ 2,256 (1) Derivative assets / liabilities related to cash flow hedges, fair value hedges and derivative instruments held for purposes other than for trading are recorded in other assets / interest, taxes and other liabilities on the consolidated balance sheet. (2) Over-the-counter ("OTC") derivatives include derivatives executed and settled bilaterally with counterparties without the use of an organized exchange or central clearing house. The credit risk associated with bilateral OTC derivatives is managed through obtaining collateral and enforceable master netting agreements. OTC-cleared derivatives are executed bilaterally in the OTC market but then novated to a central clearing counterparty, whereby the central clearing counterparty becomes the counterparty to each of the original counterparties. Exchange traded derivatives are executed directly on an organized exchange. Credit risk is minimized for OTC-cleared derivatives and exchange traded derivatives through daily margining requirements. In addition, OTC-cleared interest-rate derivatives with certain central clearing counterparties are settled daily. (3) Trading related derivative assets / liabilities are recorded in trading assets / trading liabilities on the consolidated balance sheet. (4) Consists of swap agreements entered into in conjunction with the sales of Visa Inc. ("Visa") Class B common shares ("Class B Shares"). (5) Represents the netting of derivative receivable and payable balances for the same counterparty under enforceable netting agreements. (6) Represents the netting of cash collateral posted and received by counterparty under enforceable netting agreements. (7) Netting is performed at a counterparty level in cases where enforceable master netting agreements are in place, regardless of the type of derivative instrument. Therefore, we have not allocated netting to the different types of derivative instruments shown in the table above.
Schedule of Gains and Losses on Fair Value Hedging Instruments	The following table presents the carrying amount of hedged items in fair value hedges recognized in the consolidated balance sheet at June 30, 2019 , along with the cumulative amount of fair value hedging adjustments included in the carrying amount of those hedged items: Carrying Amount of Hedged Items (1) Cumulative Amount of Fair Value Hedging Adjustments Increasing (Decreasing) the Carrying Amount of Hedged Items Active Discontinued Total (in millions) At June 30, 2019 Securities available-for-sale ("AFS") $ 11,745 $ 716 $ 252 $ 968 Long-term debt 11,964 294 (52 ) 242 (1) The carrying amount of securities AFS represents the amortized cost basis. The following table presents information on gains and losses on derivative instruments designated and qualifying as hedging instruments and the hedged items in fair value hedges and their locations on the consolidated statement of income: Gain (Loss) on Derivatives (1) Gain (Loss) on Hedged Items (1) Net Ineffective Gain (Loss) Recognized (1) Net Interest Income Other Income (Loss) Net Interest Income Other Income (Loss) Other Income (Loss) (in millions) Three Months Ended June 30, 2019 Interest rate contracts / Securities AFS $ (404 ) $ — $ 488 $ — $ — Interest rate contracts / Long-term debt 153 — (290 ) — — Total $ (251 ) $ — $ 198 $ — $ — Three Months Ended June 30, 2018 Interest rate contracts / Securities AFS $ (10 ) $ 125 $ 89 $ (117 ) $ 8 Interest rate contracts / Long-term debt (14 ) (7 ) (53 ) 4 (3 ) Total $ (24 ) $ 118 $ 36 $ (113 ) $ 5 Six Months Ended June 30, 2019 Interest rate contracts / Securities AFS $ (661 ) $ — $ 838 $ — $ — Interest rate contracts / Long-term debt 237 — (489 ) — — Total $ (424 ) $ — $ 349 $ — $ — Six Months Ended June 30, 2018 Interest rate contracts / Securities AFS $ (33 ) $ 487 $ 176 $ (474 ) $ 13 Interest rate contracts / Long-term debt (20 ) (67 ) (110 ) 65 (2 ) Total $ (53 ) $ 420 $ 66 $ (409 ) $ 11 (1) As a result of adopting new accounting guidance discussed in Note 21, "New Accounting Pronouncements," beginning January 1, 2019, we report gains and losses on the derivatives and the hedged items in fair value hedges in net interest income. Prior to January 1, 2019, fair value hedge ineffectiveness was separately measured and reported in other income (loss).
Schedule of Gains and Losses on Cash Flow Hedging Instruments	The following table presents information on gains and losses on derivative instruments designated and qualifying as hedging instruments in cash flow hedges (including amounts recognized in AOCI from discontinued cash flow hedges) and their locations on the consolidated statement of income: Gain (Loss) Recognized in AOCI on Derivatives (1) Location of Gain (Loss) Reclassified from AOCI into Income (1) Gain (Loss) Reclassified From AOCI into Income (1) 2019 2018 2019 2018 (in millions) Three Months Ended June 30, Foreign exchange contracts $ — $ (1 ) Net interest income $ — $ — Interest rate contracts (2 ) 9 Net interest income (9 ) (5 ) Total $ (2 ) $ 8 $ (9 ) $ (5 ) Six Months Ended June 30, Foreign exchange contracts $ 1 $ (6 ) Net interest income $ — $ — Interest rate contracts 5 12 Net interest income (19 ) (9 ) Total $ 6 $ 6 $ (19 ) $ (9 ) (1) As a result of adopting new accounting guidance discussed in Note 21, "New Accounting Pronouncements," beginning January 1, 2019, gains and losses on the derivatives in cash flow hedges are initially reported in AOCI and then reclassified into earnings in the same accounting period in which the designated forecasted transaction or hedged item affects earnings. Prior to January 1, 2019, cash flow hedge ineffectiveness was separately measured and reported immediately in other income (loss). Cash flow hedge ineffectiveness was immaterial during the three and six months ended June 30, 2018 .
Schedule of Gains and Losses on Derivative Instruments Included in Trading Activities	The following table presents information on gains and losses on derivative instruments held for trading purposes and their locations on the consolidated statement of income: Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest rate contracts Trading revenue $ (171 ) $ 126 $ (115 ) $ 329 Foreign exchange contracts Trading revenue 677 28 814 (72 ) Equity contracts Trading revenue (61 ) 2 (150 ) (1 ) Precious metals contracts Trading revenue (388 ) 85 (522 ) 215 Credit contracts Trading revenue (145 ) (1 ) (267 ) (4 ) Total $ (88 ) $ 240 $ (240 ) $ 467
Schedule of Gains and Losses on Derivative Instruments Held for Non-qualifying Hedging Activities	The following table presents information on gains and losses on derivative instruments held for non-qualifying hedging and other activities and their locations on the consolidated statement of income: Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest rate contracts Gain (loss) on instruments designated at fair value and related derivatives $ 180 $ (54 ) $ 336 $ (216 ) Interest rate contracts Other income (loss) (1 ) — (2 ) — Foreign exchange contracts Gain (loss) on instruments designated at fair value and related derivatives 1 (8 ) — (10 ) Equity contracts Gain (loss) on instruments designated at fair value and related derivatives 324 167 1,238 (172 ) Credit contracts Other income (loss) (4 ) 12 (14 ) 10 Other contracts (1) Other income (loss) (3 ) (12 ) (9 ) (14 ) Total $ 497 $ 105 $ 1,549 $ (402 ) (1) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares.
Credit-Risk Related Contingent Features	The following table presents the amount of additional collateral that we would be required to post (from the current collateral level) related to derivative instruments with credit-risk related contingent features if our long-term ratings were downgraded by one or two notches. A downgrade by a single rating agency that does not result in a rating lower than a preexisting corresponding rating provided by another rating agency will generally not result in additional collateral. One-notch downgrade Two-notch downgrade (in millions) Amount of additional collateral to be posted upon downgrade $ 34 $ 55
Notional Value of Derivative Contracts	The following table summarizes the notional values of derivative contracts: June 30, 2019 December 31, 2018 (in millions) Interest rate: Futures and forwards $ 653,615 $ 787,049 Swaps 3,062,626 3,203,048 Options written 106,238 106,009 Options purchased 110,682 107,561 3,933,161 4,203,667 Foreign exchange: Swaps, futures and forwards 1,169,693 1,052,088 Options written 54,583 30,567 Options purchased 55,027 31,069 Spot 42,539 31,084 1,321,842 1,144,808 Commodities, equities and precious metals: Swaps, futures and forwards 56,428 41,328 Options written 35,191 28,595 Options purchased 46,245 40,236 137,864 110,159 Credit derivatives 122,874 97,298 Other contracts (1) 969 736 Total $ 5,516,710 $ 5,556,668 (1) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares.

Fair Value Option (Tables)

Fair Value Option (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Option [Abstract]
Fair Value, Option, Quantitative Disclosures	The following table summarizes the fair value and unpaid principal balance for items we account for under FVO: Fair Value Unpaid Principal Balance Fair Value Over (Under) Unpaid Principal Balance (in millions) At June 30, 2019 Commercial loans held for sale $ 128 $ 136 $ (8 ) Securities sold under repurchase agreements 222 222 — Fixed rate long-term debt 2,160 1,750 410 Hybrid instruments: Structured deposits 8,455 8,472 (17 ) Structured notes 9,819 8,998 821 At December 31, 2018 Commercial loans held for sale $ 109 $ 120 $ (11 ) Securities sold under repurchase agreements 560 560 — Fixed rate long-term debt 1,935 1,750 185 Hybrid instruments: Structured deposits 8,154 8,441 (287 ) Structured notes 9,314 9,546 (232 )
Components of Gain on Instruments at Fair Value and Related Derivatives	The following table summarizes the components of gain (loss) on instruments designated at fair value and related derivatives reflected in the consolidated statement of income for the three and six months ended June 30, 2019 and 2018 : Loans Securities Sold Under Repurchase Agreements Long-Term Debt Hybrid Instruments Total (in millions) Three Months Ended June 30, 2019 Interest rate and other components (1) $ — $ — $ (100 ) $ (422 ) $ (522 ) Credit risk component (2) — — — — — Total mark-to-market on financial instruments designated at fair value — — (100 ) (422 ) (522 ) Mark-to-market on related derivatives — — 83 413 496 Net realized gain on related long-term debt derivatives — — 9 — 9 Gain (loss) on instruments designated at fair value and related derivatives $ — $ — $ (8 ) $ (9 ) $ (17 ) Three Months Ended June 30, 2018 Interest rate and other components (1) $ — $ 1 $ 34 $ (135 ) $ (100 ) Credit risk component (2) (1 ) — — — (1 ) Total mark-to-market on financial instruments designated at fair value (1 ) 1 34 (135 ) (101 ) Mark-to-market on related derivatives — — (33 ) 127 94 Net realized gain on related long-term debt derivatives — — 11 — 11 Gain (loss) on instruments designated at fair value and related derivatives $ (1 ) $ 1 $ 12 $ (8 ) $ 4 Six Months Ended June 30, 2019 Interest rate and other components (1) $ — $ — $ (169 ) $ (1,434 ) $ (1,603 ) Credit risk component (2) 3 — — — 3 Total mark-to-market on financial instruments designated at fair value 3 — (169 ) (1,434 ) (1,600 ) Mark-to-market on related derivatives — — 136 1,419 1,555 Net realized gain on related long-term debt derivatives — — 19 — 19 Gain (loss) on instruments designated at fair value and related derivatives $ 3 $ — $ (14 ) $ (15 ) $ (26 ) Six Months Ended June 30, 2018 Interest rate and other components (1) $ — $ — $ 122 $ 307 $ 429 Credit risk component (2) 3 — — — 3 Total mark-to-market on financial instruments designated at fair value 3 — 122 307 432 Mark-to-market on related derivatives — — (110 ) (312 ) (422 ) Net realized gain on related long-term debt derivatives — — 24 — 24 Gain (loss) on instruments designated at fair value and related derivatives $ 3 $ — $ 36 $ (5 ) $ 34 (1) As it relates to hybrid instruments, interest rate and other components primarily includes interest rate, foreign exchange and equity contract risks. (2) The fair value movement on fair value option liabilities attributable to our own credit spread is recorded in other comprehensive income (loss).

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Accumulated Other Comprehensive Loss	The following table presents changes in accumulated other comprehensive loss balances: Three Months Ended June 30, 2019 2018 (in millions) Unrealized gains (losses) on investment securities: Balance at beginning of period $ (340 ) $ (494 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $73 million and $(22) million, respectively 235 (73 ) Reclassification adjustment for gains realized in net income, net of tax of $(5) and $(3) million, respectively (1) (18 ) (7 ) Amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity realized in net income, net of tax of $1 million and $1 million, respectively (2) 3 4 Total other comprehensive income (loss) for period 220 (76 ) Balance at end of period (120 ) (570 ) Unrealized gains (losses) on fair value option liabilities attributable to our own credit spread: Balance at beginning of period 190 (11 ) Other comprehensive income (loss) for period: Net unrealized gains arising during the period, net of tax of $2 million and $41 million, respectively 7 129 Total other comprehensive income for period 7 129 Balance at end of period 197 118 Unrealized gains (losses) on derivatives designated as cash flow hedges: Balance at beginning of period (145 ) (197 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $(1) million and $2 million, respectively (1 ) 6 Reclassification adjustment for losses realized in net income, net of tax of $3 million and $1 million, respectively (3) 6 4 Total other comprehensive income for period 5 10 Balance at end of period (140 ) (187 ) Pension and postretirement benefit liability: Balance at beginning of period 8 4 Other comprehensive income (loss) for period: Change in unfunded pension and postretirement liability, net of tax of nil and less than $1 million, respectively — (1 ) Total other comprehensive loss for period — (1 ) Balance at end of period 8 3 Total accumulated other comprehensive loss at end of period $ (55 ) $ (636 ) Six Months Ended June 30, 2019 2018 (in millions) Unrealized gains (losses) on investment securities: Balance at beginning of period $ (519 ) $ (250 ) Cumulative effect adjustment to initially apply new accounting guidance for equity investments which were previously classified as available-for-sale, net of tax of $2 million (4) — 4 Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — (53 ) Balance at beginning of period, adjusted (519 ) (299 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $128 million and $(85) million, respectively 415 (266 ) Reclassification adjustment for gains realized in net income, net of tax of $(7) million and $(4) million, respectively (1) (23 ) (11 ) Amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity realized in net income, net of tax of $2 million and $2 million, respectively (2) 7 6 Total other comprehensive income (loss) for period 399 (271 ) Balance at end of period (120 ) (570 ) Unrealized gains (losses) on fair value option liabilities attributable to our own credit spread: Balance at beginning of period 301 (19 ) Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — (4 ) Balance at beginning of period, adjusted 301 (23 ) Other comprehensive income (loss) for period: Net unrealized gains (losses) arising during period, net of tax of $(33) million and $46 million, respectively (104 ) 141 Total other comprehensive income (loss) for period (104 ) 141 Balance at end of period 197 118 Unrealized gains (losses) on derivatives designated as cash flow hedges: Balance at beginning of period (159 ) (164 ) Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — (35 ) Balance at beginning of period, adjusted (159 ) (199 ) Other comprehensive income (loss) for period: Net unrealized gains arising during period, net of tax of $1 million and $2 million, respectively 5 5 Reclassification adjustment for losses realized in net income, net of tax of $5 million and $2 million, respectively (3) 14 7 Total other comprehensive income for period 19 12 Balance at end of period (140 ) (187 ) Pension and postretirement benefit liability: Balance at beginning of period 11 2 Cumulative effect adjustment to initially apply new accounting guidance for stranded tax effects resulting from Tax Legislation (4) — 1 Balance at beginning of period, adjusted 11 3 Other comprehensive income (loss) for period: Change in unfunded pension and postretirement liability, net of tax of $(1) million and less than $1 million, respectively (3 ) — Total other comprehensive loss for period (3 ) — Balance at end of period 8 3 Total accumulated other comprehensive loss at end of period $ (55 ) $ (636 ) (1) Amount reclassified to net income is included in other securities gains, net in our consolidated statement of income. (2) Amount amortized to net income is included in interest income in our consolidated statement of income. During 2014, we transferred securities from available-for-sale to held-to-maturity. At the date of transfer, AOCI included net pretax unrealized losses related to the transferred securities which are being amortized over the remaining contractual life of each security as an adjustment of yield in a manner consistent with the amortization of any premium or discount. (3) Amount reclassified to net income is included in net interest income in our consolidated statement of income. (4) See Note 2, "Summary of Significant Accounting Polices and New Accounting Pronouncements," in our 2018 Form 10-K for additional discussion.

Pension and Other Postretirem_2

Pension and Other Postretirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2019
HSBC North America Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Components of Net Periodic Benefit Cost	The table below reflects the portion of pension expense and its related components of the combined HSBC North America Pension Plan (either the "HSBC North America Pension Plan" or the "Plan") which has been allocated to us and is recorded in our consolidated statement of income. We have not been allocated any portion of the Plan's net pension liability. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest cost on projected benefit obligation $ 14 $ 15 $ 29 $ 30 Expected return on plan assets (19 ) (19 ) (37 ) (40 ) Amortization of net actuarial loss 5 5 12 10 Administrative costs 1 1 2 2 Pension expense $ 1 $ 2 $ 6 $ 2
Postretirement Plans Other Than Pensions [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Components of Net Periodic Benefit Cost	The following table reflects the components of the net periodic postretirement benefit cost: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Interest cost on accumulated benefit obligation $ 1 $ 1 $ 1 $ 1 Amortization of net actuarial gain (1 ) — (1 ) — Net periodic postretirement benefit cost $ — $ 1 $ — $ 1

Fee Income from Contracts wit_2

Fee Income from Contracts with Customers (Tables)	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Fee Income	The following table summarizes fee income from contracts with customers disaggregated by type of activity, as well as a reconciliation to total other revenues, during the three and six months ended June 30, 2019 and 2018 . See Note 21, "Fee Income from Contracts with Customers," in our 2018 Form 10-K for a description of the various types of fee-based activities and how revenue associated with these activities is recognized. There have been no significant changes in these activities since December 31, 2018 . Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Credit card fees, net $ 18 $ 15 $ 30 $ 26 Trust and investment management fees 31 34 61 72 Other fees and commissions: Account services (1) 68 79 133 148 Credit facilities 81 86 150 164 Other fees (1) 13 19 26 32 Total other fees and commissions 162 184 309 344 Servicing and other fees from HSBC affiliates 88 87 169 186 Insurance (2) 4 3 6 6 Total fee income from contracts with customers 303 323 575 634 Other non-fee revenues 133 214 251 416 Total other revenues (3) $ 436 $ 537 $ 826 $ 1,050 (1) During the fourth quarter of 2018, we concluded that certain wire transfer fees would be better presented in account services as opposed to other fees. As a result, we have reclassified $6 million and $ 10 million of wire transfer fees from other fees to account services during the three and six months ended June 30, 2018 to conform with the current year presentation. (2) Included within other income (loss) in the consolidated statement of income. (3) See Note 15, "Business Segments," for a reconciliation of total other revenues on a U.S. GAAP basis to other operating income for each business segment under the Group Reporting Basis.

Related Party Transactions (Tab

Related Party Transactions (Tables)	6 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Summary of Related Party Transactions	The following tables and discussions below present the more significant related party balances and the income (expense) generated by related party transactions: June 30, 2019 December 31, 2018 (in millions) Assets: Cash and due from banks $ 250 $ 245 Interest bearing deposits with banks 790 1,000 Trading assets 298 102 Loans 3,096 2,274 Other (1) 289 169 Total assets $ 4,723 $ 3,790 Liabilities: Deposits $ 13,301 $ 12,000 Trading liabilities 157 349 Short-term borrowings 1,518 638 Long-term debt 7,847 7,845 Other (1) 392 333 Total liabilities $ 23,215 $ 21,165 (1) Other assets and other liabilities primarily consist of derivative balances associated with hedging activities and other miscellaneous account receivables and payables. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Income (Expense): Interest income $ 47 $ 24 $ 90 $ 46 Interest expense (152 ) (90 ) (276 ) (168 ) Net interest expense (105 ) (66 ) (186 ) (122 ) Trading revenue (expense) (9 ) (627 ) (1,523 ) 531 Servicing and other fees from HSBC affiliates: HSBC Bank plc 46 43 81 84 HSBC Markets (USA) Inc. ("HMUS") 27 30 57 61 Other HSBC affiliates 15 14 31 41 Total servicing and other fees from HSBC affiliates 88 87 169 186 Gain (loss) on instruments designated at fair value and related derivatives 412 135 1,420 (303 ) Support services from HSBC affiliates: HSBC Technology & Services (USA) ("HTSU") (298 ) (310 ) (575 ) (608 ) HMUS (23 ) (25 ) (50 ) (56 ) Other HSBC affiliates (90 ) (70 ) (166 ) (152 ) Total support services from HSBC affiliates (411 ) (405 ) (791 ) (816 ) Rental income from HSBC affiliates, net (1) 12 14 24 26 Stock based compensation expense (2) (8 ) (10 ) (14 ) (15 ) (1) We receive rental income from our affiliates, and in some cases pay rental expense to our affiliates, for rent on certain office space. Net rental income from our affiliates is recorded as a component of occupancy expense, net in our consolidated statement of income. (2) Employees may participate in one or more stock compensation plans sponsored by HSBC. These expenses are included in salaries and employee benefits in our consolidated statement of income. Certain employees are also eligible to participate in a defined benefit pension plan and other postretirement plans sponsored by HSBC North America which are discussed in Note 12, "Pension and Other Postretirement Benefits."
Schedule of Assets by Related Party	At June 30, 2019 and December 31, 2018 , we had the following loan balances outstanding with HSBC affiliates: June 30, 2019 December 31, 2018 (in millions) HMUS and subsidiaries $ 2,835 $ 2,235 HSBC Bank Canada 250 — Other short-term affiliate lending 11 39 Total loans $ 3,096 $ 2,274

Business Segments (Tables)

Business Segments (Tables)	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Summary on Reconciliation of Results under Group Reporting Basis to US GAAP	The following table summarizes the results for each segment on a Group Reporting Basis, as well as provides a reconciliation of total results under the Group Reporting Basis to U.S. GAAP consolidated totals: Group Reporting Basis Consolidated Amounts RBWM CMB GB&M PB CC Total Group Reporting Basis Adjustments (1) Group Reporting Basis Reclassi- fications (2) U.S. GAAP Consolidated Totals (in millions) Three Months Ended June 30, 2019 Net interest income $ 217 $ 202 $ 136 $ 37 $ 18 $ 610 $ 3 $ (73 ) $ 540 Other operating income 74 55 170 17 49 365 (3 ) 74 436 Total operating income 291 257 306 54 67 975 — 1 976 Expected credit losses / provision for credit losses 12 9 2 2 — 25 23 (2 ) 46 279 248 304 52 67 950 (23 ) 3 930 Operating expenses 305 142 210 56 48 761 10 3 774 Profit (loss) before income tax expense $ (26 ) $ 106 $ 94 $ (4 ) $ 19 $ 189 $ (33 ) $ — $ 156 Three Months Ended June 30, 2018 Net interest income $ 225 $ 195 $ 151 $ 43 $ 18 $ 632 $ 6 $ (83 ) $ 555 Other operating income 71 58 252 16 72 469 (9 ) 77 537 Total operating income 296 253 403 59 90 1,101 (3 ) (6 ) 1,092 Expected credit losses / provision for credit losses 3 (36 ) (143 ) — 1 (175 ) 118 12 (45 ) 293 289 546 59 89 1,276 (121 ) (18 ) 1,137 Operating expenses 341 139 209 61 54 804 — (18 ) 786 Profit (loss) before income tax expense $ (48 ) $ 150 $ 337 $ (2 ) $ 35 $ 472 $ (121 ) $ — $ 351 Six Months Ended June 30, 2019 Net interest income $ 438 $ 403 $ 287 $ 74 $ 32 $ 1,234 $ 9 $ (141 ) $ 1,102 Other operating income 139 113 345 33 73 703 (20 ) 143 826 Total operating income 577 516 632 107 105 1,937 (11 ) 2 1,928 Expected credit losses / provision for credit losses 33 15 (15 ) 1 1 35 64 5 104 544 501 647 106 104 1,902 (75 ) (3 ) 1,824 Operating expenses 616 280 416 109 88 1,509 18 (3 ) 1,524 Profit (loss) before income tax expense $ (72 ) $ 221 $ 231 $ (3 ) $ 16 $ 393 $ (93 ) $ — $ 300 Balances at end of period: Total assets $ 18,907 $ 26,735 $ 87,114 $ 6,952 $ 76,055 $ 215,763 $ (31,700 ) $ — $ 184,063 Total loans, net 17,031 25,513 19,599 5,863 2,322 70,328 (2,340 ) 3,877 71,865 Goodwill 581 358 — 321 — 1,260 347 — 1,607 Total deposits 33,606 23,554 29,674 7,226 6,021 100,081 (3,434 ) 20,314 116,961 Group Reporting Basis Consolidated Amounts RBWM CMB GB&M PB CC Total Group Reporting Basis Adjustments (1) Group Reporting Basis Reclassi- fications (2) U.S. GAAP Consolidated Totals (in millions) Six Months Ended June 30, 2018 Net interest income $ 441 $ 381 $ 300 $ 90 $ 33 $ 1,245 $ 14 $ (152 ) $ 1,107 Other operating income 164 113 449 36 155 917 (20 ) 153 1,050 Total operating income 605 494 749 126 188 2,162 (6 ) 1 2,157 Expected credit losses / provision for credit losses 6 (46 ) (157 ) (3 ) 4 (196 ) 67 13 (116 ) 599 540 906 129 184 2,358 (73 ) (12 ) 2,273 Operating expenses 666 290 425 122 586 2,089 (9 ) (12 ) 2,068 Profit (loss) before income tax expense $ (67 ) $ 250 $ 481 $ 7 $ (402 ) $ 269 $ (64 ) $ — $ 205 Balances at end of period: Total assets $ 18,691 $ 23,851 $ 79,535 $ 7,075 $ 85,703 $ 214,855 $ (34,168 ) $ — $ 180,687 Total loans, net 16,695 22,879 17,786 6,036 1,865 65,261 (1,341 ) 1,948 65,868 Goodwill 581 358 — 321 — 1,260 347 — 1,607 Total deposits 32,672 23,643 32,749 8,112 4,553 101,729 (3,168 ) 15,794 114,355 (1) Represents adjustments associated with differences between U.S. GAAP and the Group Reporting Basis. (2) Represents differences in financial statement presentation between U.S. GAAP and the Group Reporting Basis.

Retained Earnings and Regulat_2

Retained Earnings and Regulatory Capital Requirements (Tables)	6 Months Ended
	Jun. 30, 2019
Banking and Thrift [Abstract]
Capital Amounts and Ratios in Accordance With Current Banking Regulations	The following table summarizes the capital amounts and ratios of HSBC USA and HSBC Bank USA, calculated in accordance with the Basel III rule at June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 Capital Amount Well-Capitalized Ratio (1) Actual Ratio Capital Amount Well-Capitalized Ratio (1) Actual Ratio (dollars are in millions) Common equity Tier 1 ratio: HSBC USA $ 15,678 4.5 % (2) 12.4 % $ 17,459 4.5 % (2) 13.6 % HSBC Bank USA 17,752 6.5 14.4 19,456 6.5 15.7 Tier 1 capital ratio: HSBC USA 16,943 6.0 13.4 18,724 6.0 14.6 HSBC Bank USA 20,252 8.0 16.5 21,956 8.0 17.7 Total capital ratio: HSBC USA 20,342 10.0 16.1 21,972 10.0 17.2 HSBC Bank USA 23,655 10.0 19.2 25,293 10.0 20.4 Tier 1 leverage ratio: HSBC USA 16,943 4.0 (2) 9.6 18,724 4.0 (2) 11.0 HSBC Bank USA 20,252 5.0 11.7 21,956 5.0 13.1 Supplementary leverage ratio ("SLR"): HSBC USA 16,943 3.0 (3) 6.8 18,724 3.0 (3) 7.6 HSBC Bank USA 20,252 3.0 (3) 8.3 21,956 3.0 (3) 9.1 Risk-weighted assets: (4) HSBC USA 126,416 127,917 HSBC Bank USA 123,021 124,112 Adjusted quarterly average assets: (5) HSBC USA 176,467 170,565 HSBC Bank USA 173,320 168,154 Total leverage exposure: (6) HSBC USA 248,581 245,796 HSBC Bank USA 243,943 242,264 (1) HSBC USA and HSBC Bank USA are categorized as "well-capitalized," as defined by their principal regulators. To be categorized as well-capitalized under regulatory guidelines, a banking institution must have the ratios reflected in the above table, and must not be subject to a directive, order, or written agreement to meet and maintain specific capital levels. (2) There are no common equity Tier 1 or Tier 1 leverage ratio components in the definition of a well-capitalized bank holding company. The ratios shown are the regulatory minimum ratios. (3) There is no SLR component in the definition of a well-capitalized banking institution. The ratios shown are the regulatory minimum ratios. (4) Calculated using the generally-applicable Standardized Approach. (5) Represents the Tier 1 leverage ratio denominator which reflects quarterly average assets adjusted for amounts permitted to be deducted from Tier 1 capital. (6) Represents the SLR denominator which includes adjusted quarterly average assets plus certain off-balance sheet exposures.

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	6 Months Ended
	Jun. 30, 2019
Variable Interest Entities [Abstract]
Summary of Assets and Liabilities Related to Consolidated Variable Interest Entities	The following table summarizes assets and liabilities related to our consolidated VIEs at June 30, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. June 30, 2019 December 31, 2018 Consolidated Assets Consolidated Liabilities Consolidated Assets Consolidated Liabilities (in millions) Low income housing limited liability partnership: Other assets $ 98 $ — $ 112 $ — Long-term debt — 66 — 66 Interest, taxes and other liabilities — 32 — 37 Total $ 98 $ 98 $ 112 $ 103
Variable Interests Held by Us and Our Maximum Exposure to Loss Rising From Our Involvements in Those VIEs	The following table provides additional information on these unconsolidated VIEs, including the variable interests held by us and our maximum exposure to loss arising from our involvements in these VIEs, at June 30, 2019 and December 31, 2018 : Total Assets Held by Unconsolidated VIEs Carrying Value of Variable Interests Held Reported as Maximum Exposure to Loss Assets Liabilities (in millions) At June 30, 2019 Structured note vehicles $ 1,526 $ 510 $ 11 $ 1,515 Limited partnership investments 2,037 542 260 570 Total $ 3,563 $ 1,052 $ 271 $ 2,085 At December 31, 2018 Structured note vehicles $ 3,033 $ 1,803 $ 20 $ 3,003 Limited partnership investments 1,578 454 209 454 Total $ 4,611 $ 2,257 $ 229 $ 3,457

Guarantee Arrangements, Pledg_2

Guarantee Arrangements, Pledged Assets and Repurchase Agreements (Tables)	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Carrying Value and Contractual Amounts of our Sell Protection Credit Derivatives and Major Off-Balance Sheet Guarantee Arrangements	The following table presents total carrying value and contractual amounts of our sell protection credit derivatives and major off-balance sheet guarantee arrangements at June 30, 2019 and December 31, 2018 . Following the table is a description of the various arrangements. June 30, 2019 December 31, 2018 Carrying Value Notional / Maximum Exposure to Loss Carrying Value Notional / Maximum Exposure to Loss (in millions) Credit derivatives (1)(2) $ (268 ) $ 54,256 $ (562 ) $ 45,384 Financial standby letters of credit, net of participations (3)(4) — 5,376 — 5,302 Performance standby letters of credit, net of participations (3)(4) — 3,489 — 3,670 Total $ (268 ) $ 63,121 $ (562 ) $ 54,356 (1) Includes $32,481 million and $25,734 million of notional issued for the benefit of HSBC affiliates at June 30, 2019 and December 31, 2018 , respectively. (2) For credit derivatives, the maximum loss is represented by the notional amounts without consideration of mitigating effects from collateral or recourse arrangements. (3) Includes $1,419 million and $1,321 million of both financial and performance standby letters of credit issued for the benefit of HSBC affiliates at June 30, 2019 and December 31, 2018 , respectively. (4) For standby letters of credit, maximum loss represents losses to be recognized assuming the letters of credit have been fully drawn and the obligors have defaulted with zero recovery.
Net Credit Derivative Positions	The following table summarizes our net credit derivative positions at June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 Carrying / Fair Value Notional Carrying / Fair Value Notional (in millions) Sell-protection credit derivative positions $ (268 ) $ 54,256 $ (562 ) $ 45,384 Buy-protection credit derivative positions 144 68,618 601 51,914 Net position (1) $ (124 ) $ 14,362 $ 39 $ 6,530 (1) Positions are presented net in the table above to provide a complete analysis of our risk exposure and depict the way we manage our credit derivative portfolio. The offset of the sell-protection credit derivatives against the buy-protection credit derivatives may not be legally binding in the absence of master netting agreements with the same counterparty. Furthermore, the credit loss triggering events for individual sell protection credit derivatives may not be the same or occur in the same period as those of the buy protection credit derivatives thereby not providing an exact offset.
Summary of Credit Ratings of Credit Risk Related Guarantees	The following table summarizes the credit ratings related to guarantees including the ratings of counterparties against which we sold credit protection and financial standby letters of credit at June 30, 2019 as an indicative proxy of payment risk: Average Life (in years) Credit Ratings of the Obligors Notional/Contractual Amounts Investment Non-Investment Grade Total (dollars are in millions) Sell-protection Credit Derivatives (1) Single name credit default swaps ("CDS") 3.0 $ 27,275 $ 13,413 $ 40,688 Index credit derivatives 4.1 5,509 6,724 12,233 Total return swaps 2.2 1,073 262 1,335 Subtotal 33,857 20,399 54,256 Standby Letters of Credit (2) 1.1 7,185 1,680 8,865 Total $ 41,042 $ 22,079 $ 63,121 (1) The credit ratings in the table represent external credit ratings for classification as investment grade and non-investment grade. (2) External ratings for most of the obligors are not available. Presented above are the internal credit ratings which are developed using similar methodologies and rating scale equivalent to external credit ratings for purposes of classification as investment grade and non-investment grade.
Summary of Change in Estimated Repurchase Liability for Loans Sold to GSEs and Other Third Parties	The following table summarizes the change in our estimated repurchase liability during the three and six months ended June 30, 2019 and 2018 for obligations arising from the breach of representations and warranties associated with mortgage loans sold: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Balance at beginning of period $ 8 $ 10 $ 8 $ 10 Decrease in liability recorded through earnings (3 ) (1 ) (3 ) (1 ) Realized losses (1 ) — (1 ) — Balance at end of period $ 4 $ 9 $ 4 $ 9
Summary of Pledged Assets Included in Consolidated Balance Sheet	Pledged assets included in the consolidated balance sheet consisted of the following: June 30, 2019 December 31, 2018 (in millions) Interest bearing deposits with banks $ 2,762 $ 3,225 Trading assets (1) 7,429 2,465 Securities available-for-sale (2) 9,048 7,440 Securities held-to-maturity (2) 2,718 1,747 Loans (3) 17,371 18,189 Other assets (4) 2,515 2,289 Total $ 41,843 $ 35,355 (1) Trading assets are primarily pledged against liabilities associated with repurchase agreements. (2) Securities are primarily pledged against derivatives, public fund deposits, trust deposits and various short-term and long term borrowings, as well as providing capacity for potential secured borrowings from the FHLB and the Federal Reserve Bank of New York. (3) Loans are primarily residential mortgage loans pledged against current and potential borrowings from the FHLB and the Federal Reserve Bank of New York. (4) Other assets represent cash on deposit with non-banks related to derivative collateral support agreements.
Offsetting Assets and Liabilities	The following table provides information about resale and repurchase agreements that are subject to offset at June 30, 2019 and December 31, 2018 : Gross Amounts Not Offset in the Balance Sheet Gross Amounts Recognized Gross Amounts Offset in the Balance Sheet (1) Net Amounts Presented in the Balance Sheet Financial Instruments (2) Cash Collateral Received / Pledged Net Amount (3) (in millions) At June 30, 2019 Assets: Securities purchased under resale agreements $ 11,602 $ 6,313 $ 5,289 $ 5,287 $ — $ 2 Liabilities: Securities sold under repurchase agreements $ 9,866 $ 6,313 $ 3,553 $ 3,553 $ — $ — At December 31, 2018 Assets: Securities purchased under resale agreements $ 12,035 $ 1,867 $ 10,168 $ 10,165 $ — $ 3 Liabilities: Securities sold under repurchase agreements $ 3,333 $ 1,867 $ 1,466 $ 1,458 $ — $ 8 (1) Represents recognized amount of resale and repurchase agreements with counterparties subject to legally enforceable netting agreements that meet the applicable netting criteria as permitted by generally accepted accounting principles. (2) Represents securities received or pledged to cover financing transaction exposures. (3) Represents the amount of our exposure that is not collateralized / covered by pledged collateral.
Class of Collateral Pledged and Remaining Contractual Maturity of Repurchase Agreements Accounted for as Secured Borrowings	The following table provides the class of collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings at June 30, 2019 and December 31, 2018 : Overnight and Continuous Up to 30 Days 31 to 90 Days 91 Days to One Year Greater Than One Year Total (in millions) At June 30, 2019 U.S. Treasury, U.S. Government sponsored and U.S. Government agency securities $ 7,075 $ 1,644 $ — $ 500 $ 500 $ 9,719 Foreign debt securities — 147 — — — 147 Total repurchase agreements accounted for as secured borrowings $ 7,075 $ 1,791 $ — $ 500 $ 500 $ 9,866 At December 31, 2018 U.S. Treasury, U.S. Government sponsored and U.S. Government agency securities $ 1,773 $ 369 $ — $ 191 $ 1,000 $ 3,333

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Recorded at Fair Value on a Recurring Basis	The following table presents information about our assets and liabilities measured at fair value on a recurring basis at June 30, 2019 and December 31, 2018 , and indicates the fair value hierarchy of the valuation techniques utilized to determine such fair value. Unless otherwise noted below, assets and liabilities in the following table are recorded at fair value through net income. Fair Value Measurements on a Recurring Basis June 30, 2019 Level 1 Level 2 Level 3 Gross Balance Netting (7) Net Balance (in millions) Assets: Trading assets, excluding derivatives: U.S. Treasury, U.S. Government agencies and sponsored enterprises $ 10,620 $ 78 $ — $ 10,698 $ — $ 10,698 Asset-backed securities: Collateralized debt obligations — — 86 86 — 86 Residential mortgages — — 16 16 — 16 Student loans — — 90 90 — 90 Corporate and other domestic debt securities — — 510 510 — 510 Debt securities issued by foreign entities 12,199 216 — 12,415 — 12,415 Equity securities 2,747 — — 2,747 — 2,747 Precious metals trading — 3,895 — 3,895 — 3,895 Derivatives: (1) Interest rate contracts 99 11,450 11 11,560 — 11,560 Foreign exchange contracts 1 13,362 7 13,370 — 13,370 Equity contracts 16 3,575 185 3,776 — 3,776 Precious metals contracts 106 1,254 — 1,360 — 1,360 Credit contracts — 1,051 68 1,119 — 1,119 Other contracts (2) — — 5 5 — 5 Derivatives netting — — — — (27,994 ) (27,994 ) Total derivatives 222 30,692 276 31,190 (27,994 ) 3,196 Securities available-for-sale: (3) U.S. Treasury, U.S. Government agencies and sponsored enterprises 19,559 14,571 — 34,130 — 34,130 Asset-backed securities: Home equity — 36 — 36 — 36 Other — — 113 113 — 113 Debt securities issued by foreign entities 2,591 384 — 2,975 — 2,975 Loans (4) — 128 — 128 — 128 Other assets: Equity securities — 193 — 193 — 193 Equity Securities measured at net asset value (5) — — — 109 — 109 Other (6) — — 1 1 — 1 Total assets $ 47,938 $ 50,193 $ 1,092 $ 99,332 $ (27,994 ) $ 71,338 Liabilities: Domestic deposits (4) $ — $ 7,525 $ 930 $ 8,455 $ — $ 8,455 Trading liabilities, excluding derivatives 834 106 — 940 — 940 Derivatives: (1) Interest rate contracts 51 12,752 1 12,804 — 12,804 Foreign exchange contracts — 13,044 8 13,052 — 13,052 Equity contracts — 2,778 123 2,901 — 2,901 Precious metals contracts 137 1,254 — 1,391 — 1,391 Credit contracts — 1,253 22 1,275 — 1,275 Other contracts (2) — — 40 40 — 40 Derivatives netting — — — — (28,182 ) (28,182 ) Total derivatives 188 31,081 194 31,463 (28,182 ) 3,281 Short-term borrowings (4) — 222 — 222 — 222 Long-term debt (4) — 11,538 441 11,979 — 11,979 Total liabilities $ 1,022 $ 50,472 $ 1,565 $ 53,059 $ (28,182 ) $ 24,877 Fair Value Measurements on a Recurring Basis December 31, 2018 Level 1 Level 2 Level 3 Gross Balance Netting (7) Net Balance (in millions) Assets: Trading assets, excluding derivatives: U.S. Treasury, U.S. Government agencies and sponsored enterprises $ 5,368 $ 152 $ — $ 5,520 $ — $ 5,520 Asset-backed securities: Collateralized debt obligations — — 100 100 — 100 Residential mortgages — — 16 16 — 16 Student loans — — 92 92 — 92 Corporate and other domestic debt securities — — 1,803 1,803 — 1,803 Debt securities issued by foreign entities 8,552 207 — 8,759 — 8,759 Equity securities 751 — — 751 — 751 Precious metals trading — 1,889 — 1,889 — 1,889 Derivatives: (1) Interest rate contracts 2 10,053 2 10,057 — 10,057 Foreign exchange contracts — 15,919 2 15,921 — 15,921 Equity contracts — 2,449 97 2,546 — 2,546 Precious metals contracts 16 829 — 845 — 845 Credit contracts — 883 73 956 — 956 Other contracts (2) — — 5 5 — 5 Derivatives netting — — — — (27,192 ) (27,192 ) Total derivatives 18 30,133 179 30,330 (27,192 ) 3,138 Securities available-for-sale: (3) U.S. Treasury, U.S. Government agencies and sponsored enterprises 16,198 11,699 — 27,897 — 27,897 Asset-backed securities: Home equity — 42 — 42 — 42 Other — — 107 107 — 107 Debt securities issued by foreign entities 2,362 971 — 3,333 — 3,333 Loans (4) — 109 — 109 — 109 Other assets: Equity securities — 190 — 190 — 190 Equity Securities measured at net asset value (5) — — — 88 — 88 Other assets (6) — — 4 4 — 4 Total assets $ 33,249 $ 45,392 $ 2,301 $ 81,030 $ (27,192 ) $ 53,838 Liabilities: Domestic deposits (4) $ — $ 7,229 $ 925 $ 8,154 $ — $ 8,154 Trading liabilities, excluding derivatives 738 215 — 953 — 953 Derivatives: (1) Interest rate contracts 45 11,140 — 11,185 — 11,185 Foreign exchange contracts 15 15,715 3 15,733 — 15,733 Equity contracts — 2,717 149 2,866 — 2,866 Precious metals contracts 274 626 — 900 — 900 Credit contracts — 926 21 947 — 947 Other contracts (2) — — 40 40 — 40 Derivatives netting — — — — (28,847 ) (28,847 ) Total derivatives 334 31,124 213 31,671 (28,847 ) 2,824 Short-term borrowings (4) — 560 — 560 — 560 Long-term debt (4) — 10,837 412 11,249 — 11,249 Total liabilities $ 1,072 $ 49,965 $ 1,550 $ 52,587 $ (28,847 ) $ 23,740 (1) Includes trading derivative assets of $3,045 million and $3,048 million and trading derivative liabilities of $3,086 million and $2,690 million at June 30, 2019 and December 31, 2018 , respectively, as well as derivatives held for hedging and commitments accounted for as derivatives. See Note 9, "Derivative Financial Instruments," for additional information. Excluding changes in fair value of a derivative instrument associated with a qualifying cash flow hedge, which are recognized initially in other comprehensive income (loss), derivative assets and liabilities are recorded at fair value through net income. (2) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares. (3) Securities available-for-sale are recorded at fair value through other comprehensive income (loss). (4) See Note 10, "Fair Value Option," for additional information. Excluding the fair value movement on fair value option liabilities attributable to our own credit spread, which is recorded in other comprehensive income (loss), fair value option assets and liabilities are recorded at fair value through net income. (5) Investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy. (6) Represents contingent consideration receivable associated with the sale of a portion of our PB business. (7) Represents counterparty and cash collateral netting which allow the offsetting of amounts relating to certain contracts if certain conditions are met.
Changes in Fair Value of Level 3 Assets and Liabilities	The following table summarizes additional information about changes in the fair value of Level 3 assets and liabilities during the three and six months ended June 30, 2019 and 2018 . As a risk management practice, we may risk manage the Level 3 assets and liabilities, in whole or in part, using securities and derivative positions that are classified as Level 1 or Level 2 measurements within the fair value hierarchy. Since those Level 1 and Level 2 risk management positions are not included in the table below, the information provided does not reflect the effect of such risk management activities related to the Level 3 assets and liabilities. Apr. 1, 2019 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2019 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 90 $ 2 $ — $ — $ — $ (6 ) $ — $ — $ 86 $ (4 ) Residential mortgage asset-backed securities 16 — — — — — — — 16 — Student loan asset-backed securities 95 — — — — (5 ) — — 90 (5 ) Corporate and other domestic debt securities 510 — — — — — — — 510 — Derivatives, net: (2) Interest rate contracts 7 8 — — — — — (5 ) 10 3 Foreign exchange contracts (1 ) — — — — — — — (1 ) — Equity contracts 24 39 — — — 1 — (2 ) 62 40 Credit contracts 53 (3 ) — — — (4 ) — — 46 (2 ) Other contracts (3) (37 ) (3 ) — — — 5 — — (35 ) — Other asset-backed securities available-for-sale (4) 109 — 4 — — — — — 113 4 Other assets (5) 1 — — — — — — — 1 — Total assets $ 867 $ 43 $ 4 $ — $ — $ (9 ) $ — $ (7 ) $ 898 $ 36 Liabilities: Domestic deposits (6) $ (949 ) $ (35 ) $ 2 $ — $ (49 ) $ 64 $ (5 ) $ 42 $ (930 ) $ (30 ) Long-term debt (6) (453 ) (15 ) 1 — (33 ) 20 — 39 (441 ) (9 ) Total liabilities $ (1,402 ) $ (50 ) $ 3 $ — $ (82 ) $ 84 $ (5 ) $ 81 $ (1,371 ) $ (39 ) Jan. 1, 2019 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2019 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 100 $ 3 $ — $ — $ — $ (17 ) $ — $ — $ 86 $ (10 ) Residential mortgage asset-backed securities 16 — — — — — — — 16 — Student loan asset-backed securities 92 5 — — — (7 ) — — 90 (2 ) Corporate and other domestic debt securities 1,803 — — — — (1,293 ) — — 510 — Derivatives, net: (2) Interest rate contracts 2 13 — — — — — (5 ) 10 8 Foreign exchange contracts (1 ) — — — — — — — (1 ) — Equity contracts (52 ) 110 — — — 5 — (1 ) 62 115 Credit contracts 52 (40 ) — — — 34 — — 46 (2 ) Other contracts (3) (35 ) (9 ) — — — 9 — — (35 ) — Other asset-backed securities available-for-sale (4) 107 — 6 — — — — — 113 6 Other assets (5) 4 — — — — (3 ) — — 1 — Total assets $ 2,088 $ 82 $ 6 $ — $ — $ (1,272 ) $ — $ (6 ) $ 898 $ 115 Liabilities: Domestic deposits (6) $ (925 ) $ (64 ) $ (3 ) $ — $ (145 ) $ 109 $ (5 ) $ 103 $ (930 ) $ (135 ) Long-term debt (6) (412 ) (43 ) (2 ) — (64 ) 33 — 47 (441 ) (61 ) Total liabilities $ (1,337 ) $ (107 ) $ (5 ) $ — $ (209 ) $ 142 $ (5 ) $ 150 $ (1,371 ) $ (196 ) Apr. 1, 2018 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2018 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 131 $ 1 $ — $ — $ — $ (1 ) $ — $ — $ 131 $ 1 Corporate and other domestic debt securities 1,803 — — — — — — — 1,803 — Derivatives, net: (2) Foreign exchange contracts — (1 ) — — — — — — (1 ) (1 ) Equity contracts 27 (10 ) — — — (16 ) (1 ) 2 2 (7 ) Credit contracts 113 1 — — — (4 ) — — 110 (3 ) Other contracts (3) (44 ) (12 ) — — — 5 — — (51 ) — Other asset-backed securities available-for-sale (4) 107 — — — — — — — 107 — Other assets (5) 15 (3 ) — — — — — — 12 — Total assets $ 2,152 $ (24 ) $ — $ — $ — $ (16 ) $ (1 ) $ 2 $ 2,113 $ (10 ) Liabilities: Domestic deposits (6) $ (916 ) $ 2 $ 5 $ — $ (88 ) $ 38 $ (10 ) $ 93 $ (876 ) $ 8 Long-term debt (6) (630 ) (5 ) 1 — (28 ) 74 — 31 (557 ) 1 Total liabilities $ (1,546 ) $ (3 ) $ 6 $ — $ (116 ) $ 112 $ (10 ) $ 124 $ (1,433 ) $ 9 Jan. 1, 2018 Total Realized / Unrealized Gains (Losses) Included in Purch- ases Issu- ances Settle- ments Transfers Into Level 3 Transfers Out of Level 3 Jun. 30, 2018 Current Period Unrealized Gains (Losses) Earnings Other Compre- hensive Income (Loss) (in millions) Assets: Trading assets, excluding derivatives: (1) Collateralized debt obligations $ 129 $ 8 $ — $ — $ — $ (6 ) $ — $ — $ 131 $ 8 Corporate and other domestic debt securities 1,803 — — — — — — — 1,803 — Derivatives, net: (2) Foreign exchange contracts — (1 ) — — — — — — (1 ) (1 ) Equity contracts 81 (50 ) — — — (30 ) (1 ) 2 2 (45 ) Credit contracts 114 2 — — — (6 ) — — 110 (4 ) Other contracts (3) (46 ) (14 ) — — — 9 — — (51 ) — Other asset-backed securities available-for-sale (4) 111 — (4 ) — — — — — 107 (4 ) Other assets (5) 15 (3 ) — — — — — — 12 — Total assets $ 2,207 $ (58 ) $ (4 ) $ — $ — $ (33 ) $ (1 ) $ 2 $ 2,113 $ (46 ) Liabilities: Domestic deposits (6) $ (897 ) $ 23 $ 3 $ — $ (179 ) $ 60 $ (13 ) $ 127 $ (876 ) $ 25 Long-term debt (6) (641 ) 6 5 — (143 ) 141 — 75 (557 ) 18 Total liabilities $ (1,538 ) $ 29 $ 8 $ — $ (322 ) $ 201 $ (13 ) $ 202 $ (1,433 ) $ 43 (1) Gains (losses) on trading assets, excluding derivatives are included in trading revenue in the consolidated statement of income. (2) Level 3 net derivatives included derivative assets of $276 million and derivative liabilities of $194 million at June 30, 2019 and derivative assets of $253 million and derivative liabilities of $193 million at June 30, 2018 . Gains (losses) on derivatives, net are predominantly included in trading revenue and gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income. (3) Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares. Gains (losses) on these swap agreements are included in other income (loss) in the consolidated statement of income. (4) Realized gains (losses) on securities available-for-sale are included in other securities gains, net in the consolidated statement of income. Unrealized gains (losses) on securities available-for-sale are included in other comprehensive income (loss). (5) Represents contingent consideration receivable associated with the sale of a portion of our PB business. Gains (losses) associated with this transaction are included in other income (loss) in the consolidated statement of income. (6) Excluding unrealized gains (losses) on fair value option liabilities attributable to our own credit spread, which are recorded in other comprehensive income (loss), gains (losses) on fair value option liabilities are included in gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income.
Quantitative Information about Recurring Fair Value Measurement of Assets and Liabilities Classified as Level 3	The following table presents quantitative information about the unobservable inputs used to determine the recurring fair value measurement of assets and liabilities classified as Level 3 fair value measurements at June 30, 2019 and December 31, 2018 : June 30, 2019 Financial Instrument Type Fair Value (in millions) Valuation Technique(s) Significant Unobservable Inputs Range of Inputs Collateralized debt obligations $ 86 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 0% - 1% Conditional default rates 0% - 1% Loss severity rates 90% - 95% Residential mortgage asset-backed securities $ 16 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 5% - 10% Conditional default rates 1% - 5% Loss severity rates 65% - 70% Discount margin 100bps - 250bps Student loan asset-backed securities $ 90 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 7% - 9% Conditional default rates 0% - 1% Loss severity rates 25% - 40% Discount margin 95bps -198bps Corporate and other domestic debt securities $ 510 Discounted cash flows Spread volatility on collateral assets 2% - 4% Correlation between insurance claim 80% Interest rate derivative contracts $ 10 Market comparable adjusted for probability to fund and, where applicable, discounted cash flows Probability to fund for rate lock commitments 38% - 96% Likelihood of transaction being executed 75% - 100% Foreign exchange derivative contracts (1) $ (1 ) Option pricing model Implied volatility of currency pairs 9% - 13% Equity derivative contracts (1) $ 62 Option pricing model Equity / Equity Index volatility 7% - 38% Equity / Equity and Equity / Index correlation 26% - 79% Equity dividend yields 0% - 4% Credit derivative contracts $ 46 Option pricing model and, where applicable, discounted cash flows Credit default swap spreads 49bps - 63bps Other derivative contracts $ (35 ) Discounted cash flows Conversion rate 1.6 times Expected duration 1 - 2 years Other asset-backed securities available-for-sale $ 113 Discounted cash flows Market assumptions related to yields for comparable instruments 1% - 3% Other assets $ 1 Discounted cash flows Client transfer rates based on rating 50% - 95% Domestic deposits (structured deposits) (1)(2) $ (930 ) Option adjusted discounted cash flows Implied volatility of currency pairs 9% - 13% Equity / Equity Index volatility 7% - 29% Equity / Equity and Equity / Index correlation 43% - 46% Long-term debt (structured notes) (1)(2) $ (441 ) Option adjusted discounted cash flows Implied volatility of currency pairs 9% - 13% Equity / Equity Index volatility 7% - 33% Equity / Equity and Equity / Index correlation 26% - 79% December 31, 2018 Financial Instrument Type Fair Value (in millions) Valuation Technique(s) Significant Unobservable Inputs Range of Inputs Collateralized debt obligations $ 100 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 0% - 1% Conditional default rates 0% - 1% Loss severity rates 90% - 95% Residential mortgage asset-backed securities $ 16 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 0% - 5% Conditional default rates 1% - 4% Loss severity rates 80% - 85% Discount margin 100bps - 250bps Student loan asset-backed securities $ 92 Broker quotes or consensus pricing and, where applicable, discounted cash flows Prepayment rates 6% - 7% Conditional default rates 1% - 2% Loss severity rates 25% - 40% Discount margin 91bps -115bps Corporate and other domestic debt securities $ 1,803 Discounted cash flows Spread volatility on collateral assets 2% - 4% Correlation between insurance claim shortfall and collateral value 80% Interest rate derivative contracts $ 2 Market comparable adjusted for probability to fund and, where applicable, discounted cash flows Probability to fund for rate lock commitments 3% - 99% Likelihood of transaction being executed 75% - 100% Foreign exchange derivative contracts (1) $ (1 ) Option pricing model Implied volatility of currency pairs 8% - 12% Equity derivative contracts (1) $ (52 ) Option pricing model Equity / Equity Index volatility 7% - 44% Equity / Equity and Equity / Index correlation 42% - 79% Equity dividend yields 0% - 7% Credit derivative contracts $ 52 Option pricing model and, where applicable, discounted cash flows Credit default swap spreads 102bps - 118bps Other derivative contracts $ (35 ) Discounted cash flows Conversion rate 1.6 times Expected duration 2 - 3 years Other asset-backed securities available-for-sale $ 107 Discounted cash flows Market assumptions related to yields for comparable instruments 1% - 3% Other assets $ 4 Discounted cash flows Client transfer rates based on rating 50% - 95% Domestic deposits (structured deposits) (1)(2) $ (925 ) Option adjusted discounted cash flows Implied volatility of currency pairs 8% - 12% Equity / Equity Index volatility 7% - 37% Equity / Equity and Equity / Index correlation 42% - 49% Long-term debt (structured notes) (1)(2) $ (412 ) Option adjusted discounted cash flows Implied volatility of currency pairs 8% - 12% Equity / Equity Index volatility 7% - 42% Equity / Equity and Equity / Index correlation 45% - 79% (1) We are the client-facing entity and we enter into identical but opposite derivatives to transfer the resultant risks to our affiliates. With the exception of counterparty credit risks, we are market neutral. The corresponding intra-group derivatives are presented as equity derivatives and foreign exchange derivatives in the table. (2) Structured deposits and structured notes contain embedded derivative features whose fair value measurements contain significant Level 3 inputs.
Assets and Liabilities Recorded at Fair Value on a Non Recurring Basis	The following table presents the fair value hierarchy level within which the fair value of the financial and non-financial assets has been recorded at June 30, 2019 and December 31, 2018 . The gains (losses) during the three and six months ended June 30, 2019 and 2018 are also included. Non-Recurring Fair Value Measurements Total Gains (Losses) For the Three Months Ended June 30, 2019 Total Gains (Losses) For the Six Months Ended June 31, 2019 Level 1 Level 2 Level 3 Total (in millions) Residential mortgage loans held for sale (1) $ — $ 6 $ — $ 6 $ — $ — Consumer loans (2) — 11 — 11 (2 ) (4 ) Impaired commercial loans (3) — — 30 30 — (1 ) Real estate owned (4) — 5 — 5 — — Total assets at fair value on a non-recurring basis $ — $ 22 $ 30 $ 52 $ (2 ) $ (5 ) Non-Recurring Fair Value Measurements Total Gains (Losses) For the Three Months Ended June 30, 2018 Total Gains (Losses) Months Ended Level 1 Level 2 Level 3 Total (in millions) Consumer loans (2) $ — $ 15 $ — $ 15 $ (1 ) $ (2 ) Commercial loans held for sale (5) — 36 — 36 — 3 Impaired commercial loans (3) — — 37 37 46 101 Real estate owned (4) — 7 — 7 1 2 Total assets at fair value on a non-recurring basis $ — $ 58 $ 37 $ 95 $ 46 $ 104 (1) At June 30, 2019 , the fair value of the loans held for sale was below cost. (2) Represents residential mortgage loans held for investment whose carrying amount was reduced during the periods presented based on the fair value of the underlying collateral. (3) Certain commercial loans have undergone troubled debt restructurings and are considered impaired. As a matter of practical expedient, we measure the credit impairment of a collateral-dependent loan based on the fair value of the collateral asset. The collateral often involves real estate properties that are illiquid due to market conditions. As a result, these loans are classified as a Level 3 fair value measurement within the fair value hierarchy. (4) Real estate owned is required to be reported on the balance sheet net of transactions costs. The real estate owned amounts in the table above reflect the fair value unadjusted for transaction costs. (5) At December 31, 2018 , the fair value of the loans held for sale was below cost.
Quantitative Information about Non Recurring Fair Value Measurement of Assets and Liabilities	The following tables present quantitative information about non-recurring fair value measurements of assets and liabilities classified with Level 3 of the fair value hierarchy at June 30, 2019 and December 31, 2018 : At June 30, 2019 Financial Instrument Type Fair Value (in millions) Valuation Technique(s) Significant Unobservable Inputs Range of Inputs Impaired commercial loans $ 30 Valuation of third party appraisal Loss severity rates 0% - 65% At December 31, 2018 Financial Instrument Type Fair Value (in millions) Valuation Technique(s) Significant Unobservable Inputs Range of Inputs Impaired commercial loans $ 37 Valuation of third party appraisal Loss severity rates 13% - 100%
Additional Information Relating to Asset-Backed Securities and Collateralized Debt Obligations	The following tables provide additional information relating to our asset-backed securities, including certain CDOs, at June 30, 2019 : Trading asset-backed securities: Rating of Securities: (1) Collateral Type: Level 3 Total (in millions) AAA - A Collateralized debt obligations $ 54 $ 54 Student loans 90 90 Total AAA -A 144 144 BBB - B Collateralized debt obligations 32 32 CCC - Unrated Residential mortgages - Subprime 16 16 $ 192 $ 192 Available-for-sale asset-backed securities: Rating of Securities: (1) Collateral Type: Level 2 Level 3 Total (in millions) AAA - A Home equity - Alt A $ 36 $ — $ 36 Other — 53 53 Total AAA -A 36 53 89 BBB -B Other — 60 60 $ 36 $ 113 $ 149 (1) We utilize Standard and Poor's ("S&P") as the primary source of credit ratings in the tables above. If S&P ratings are not available, ratings by Moody's and Fitch are used in that order. Ratings for CDOs represent the ratings associated with the underlying collateral.
Carrying Value and Estimated Fair Value of Financial Instruments	The following table summarizes the carrying value and estimated fair value of our financial instruments, excluding financial instruments that are carried at fair value on a recurring basis, at June 30, 2019 and December 31, 2018 and their classification within the fair value hierarchy: June 30, 2019 Carrying Value Fair Value Level 1 Level 2 Level 3 (in millions) Financial assets: Short-term financial assets $ 12,963 $ 12,963 $ 1,196 $ 11,736 $ 31 Federal funds sold and securities purchased under agreements to resell 5,289 5,289 — 5,289 — Securities held-to-maturity 13,927 14,011 — 14,011 — Commercial loans, net of allowance for credit losses 52,226 54,350 — — 54,350 Commercial loans held for sale 23 23 — 23 — Consumer loans, net of allowance for credit losses 19,639 19,260 — — 19,260 Consumer loans held for sale: Residential mortgages 40 41 — 40 1 Financial liabilities: Short-term financial liabilities $ 8,458 $ 8,475 $ — $ 8,444 $ 31 Deposits: Without fixed maturities 91,305 91,305 — 91,305 — Fixed maturities 17,201 17,096 — 17,096 — Long-term debt 18,870 19,185 — 19,185 — December 31, 2018 Carrying Value Fair Value Level 1 Level 2 Level 3 (in millions) Financial assets: Short-term financial assets $ 17,237 $ 17,237 $ 1,514 $ 15,700 $ 23 Federal funds sold and securities purchased under agreements to resell 10,168 10,168 — 10,168 — Securities held-to-maturity 14,670 14,443 — 14,443 — Commercial loans, net of allowance for credit losses 48,884 50,671 — — 50,671 Commercial loans held for sale 285 285 — 285 — Consumer loans, net of allowance for credit losses 19,553 18,878 — — 18,878 Consumer loans held for sale: Residential mortgages 65 65 — 65 — Other consumer 53 53 — — 53 Financial liabilities: Short-term financial liabilities $ 3,643 $ 3,649 $ — $ 3,626 $ 23 Deposits: Without fixed maturities 91,794 91,794 — 91,794 — Fixed maturities 10,996 10,933 — 10,933 — Deposits held for sale 10 10 — 10 — Long-term debt 19,379 19,688 — 19,688 —

Trading Assets and Liabilitie_2

Trading Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	$ 33,502	$ 21,978
Trading liabilities	4,026	3,643
U.S. Treasury [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	10,620	5,368
US Government agency issued or guaranteed [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	19	111
US Government-sponsored enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	59	41
Asset-backed securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	192	208
Corporate and foreign bonds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	12,925	10,562
Equity securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	2,747	751
Precious metals [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	3,895	1,889
Trading liabilities	106	215
Securities sold, not yet purchased [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading liabilities	834	738
Derivatives, net [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading assets	3,045	3,048
Derivatives, net [Member]
Debt and Equity Securities, FV-NI [Line Items]
Trading liabilities	$ 3,086	$ 2,690

Trading Assets and Liabilitie_3

Trading Assets and Liabilities - Additional Information (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Debt and Equity Securities, FV-NI [Line Items]
Derivatives included in trading assets, amount offset	[1],[2]	$ 3,439	$ 2,020
Derivatives included in trading liabilities, amount offset	[1],[2]	3,627	3,675
Trading Assets [Member]
Debt and Equity Securities, FV-NI [Line Items]
Derivatives included in trading assets, amount offset		2,638	2,013
Trading Liabilities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Derivatives included in trading liabilities, amount offset		$ 3,627	$ 3,458
[1]	Netting is performed at a counterparty level in cases where enforceable master netting agreements are in place, regardless of the type of derivative instrument. Therefore, we have not allocated netting to the different types of derivative instruments shown in the table above.
[2]	Represents the netting of cash collateral posted and received by counterparty under enforceable netting agreements.

Securities - Amortized Cost and

Securities - Amortized Cost and Fair Value of Asset Backed Securities (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		$ 37,254	$ 31,379
Available-for-sale securities, Unrealized Losses		(368)	(758)
Available-for-sale Securities, Unrealized Gains		300	177
Available-for-sale Securities, Amortized Cost		37,322	31,960
Securities held-to-maturity, fair value		14,011	14,443
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		(51)	(299)
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		135	72
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		13,927	14,670
US Treasury Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		16,826	13,290
Available-for-sale securities, Unrealized Losses		(264)	(365)
Available-for-sale Securities, Unrealized Gains		148	106
Available-for-sale Securities, Amortized Cost		16,942	13,549
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		4,827	5,393
Available-for-sale securities, Unrealized Losses		(26)	(154)
Available-for-sale Securities, Unrealized Gains		76	6
Available-for-sale Securities, Amortized Cost		4,777	5,541
Securities held-to-maturity, fair value		1,855	1,779
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		(3)	(34)
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		15	1
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		1,843	1,812
Collateralized Mortgage Obligations, Issued by U.S. Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		681	652
Available-for-sale securities, Unrealized Losses		(5)	(35)
Available-for-sale Securities, Unrealized Gains		2	1
Available-for-sale Securities, Amortized Cost		684	686
Securities held-to-maturity, fair value		1,757	1,886
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		(7)	(26)
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		46	34
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		1,718	1,878
Direct Agency Obligations U S Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		2,779	2,866
Available-for-sale securities, Unrealized Losses		(1)	(2)
Available-for-sale Securities, Unrealized Gains		29	37
Available-for-sale Securities, Amortized Cost		2,751	2,831
Mortgage-backed Securities, Issued or Guaranteed by US Government Agency [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		7,797	4,272
Available-for-sale securities, Unrealized Losses		(61)	(171)
Available-for-sale Securities, Unrealized Gains		24	1
Available-for-sale Securities, Amortized Cost		7,834	4,442
Securities held-to-maturity, fair value		2,183	2,043
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		(2)	(63)
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		6	2
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		2,179	2,104
Collateralized Mortgage Obligations, Issued or Guaranteed by US Government Agency [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		967	1,120
Available-for-sale securities, Unrealized Losses		(7)	(29)
Available-for-sale Securities, Unrealized Gains		10	9
Available-for-sale Securities, Amortized Cost		964	1,140
Securities held-to-maturity, fair value		8,202	8,722
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		(39)	(176)
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		67	35
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		8,174	8,863
Direct Agency Obligations, Issued or Guaranteed by US Government Agency [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		253	304
Available-for-sale securities, Unrealized Losses		(1)	0
Available-for-sale Securities, Unrealized Gains		2	9
Available-for-sale Securities, Amortized Cost		252	295
Obligations of U.S. states and political subdivision [Member]
Debt Securities, Available-for-sale [Line Items]
Securities held-to-maturity, fair value		12	11
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		1	0
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		11	11
Residential Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Securities held-to-maturity, fair value		2	2
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss		0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		0	0
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment		2	2
Home Equity Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		36	42
Available-for-sale securities, Unrealized Losses		(3)	(2)
Available-for-sale Securities, Unrealized Gains		0	0
Available-for-sale Securities, Amortized Cost		39	44
Other securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities		113	107
Available-for-sale securities, Unrealized Losses		0	0
Available-for-sale Securities, Unrealized Gains		5	5
Available-for-sale Securities, Amortized Cost		108	102
Foreign Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	[1]	2,975	3,333
Available-for-sale securities, Unrealized Losses	[1]	0	0
Available-for-sale Securities, Unrealized Gains	[1]	4	3
Available-for-sale Securities, Amortized Cost	[1]	$ 2,971	$ 3,330
[1]	Foreign debt securities represent public sector entity, bank or corporate debt.

Securities - Gross unrealized l

Securities - Gross unrealized losses and related fair values (Detail) $ in Millions	Jun. 30, 2019USD ($)security	Dec. 31, 2018USD ($)security
Debt Securities, Available-for-sale [Line Items]
Number of securities available for sale in one year or less | security	38	88
Securities available-for-sale gross unrealized losses one year or less	$ (37)	$ (20)
Securities available-for-sale aggregate fair value of investment one year or less	$ 5,521	$ 3,381
Number of Securities available for sale greater than one year | security	218	276
Securities available-for-sale gross unrealized losses greater than one year	$ (331)	$ (738)
Securities available-for-sale agregate fair value of investment greater than one year	$ 12,837	$ 17,393
Number of securities held-to-maturity in one year or less | security	44	215
Securities held-to-maturity gross unrealized losses one year or less	$ 0	$ (22)
Securities held-to-maturity aggregate fair value of investment one year or less	$ 190	$ 1,453
Number of securities held-to-maturity greater than one year | security	688	1,003
Securities held-to-maturity gross unrealized losses greater than one year	$ (51)	$ (277)
Securities held-to-maturity aggregate fair value of investment greater than one year	$ 5,979	$ 9,111
US Treasury Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities available for sale in one year or less | security	17	8
Securities available-for-sale gross unrealized losses one year or less	$ (31)	$ (12)
Securities available-for-sale aggregate fair value of investment one year or less	$ 3,652	$ 1,013
Number of Securities available for sale greater than one year | security	32	41
Securities available-for-sale gross unrealized losses greater than one year	$ (233)	$ (353)
Securities available-for-sale agregate fair value of investment greater than one year	$ 6,030	$ 8,828
US Government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities available for sale in one year or less | security	1	55
Securities available-for-sale gross unrealized losses one year or less	$ 0	$ (6)
Securities available-for-sale aggregate fair value of investment one year or less	$ 252	$ 538
Number of Securities available for sale greater than one year | security	122	159
Securities available-for-sale gross unrealized losses greater than one year	$ (32)	$ (185)
Securities available-for-sale agregate fair value of investment greater than one year	$ 2,678	$ 3,698
Number of securities held-to-maturity in one year or less | security	12	103
Securities held-to-maturity gross unrealized losses one year or less	$ 0	$ (8)
Securities held-to-maturity aggregate fair value of investment one year or less	$ 3	$ 684
Number of securities held-to-maturity greater than one year | security	301	511
Securities held-to-maturity gross unrealized losses greater than one year	$ (10)	$ (52)
Securities held-to-maturity aggregate fair value of investment greater than one year	$ 1,210	$ 1,739
US Government agency issued or guaranteed [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities available for sale in one year or less | security	2	8
Securities available-for-sale gross unrealized losses one year or less	$ (6)	$ (2)
Securities available-for-sale aggregate fair value of investment one year or less	$ 177	$ 106
Number of Securities available for sale greater than one year | security	59	72
Securities available-for-sale gross unrealized losses greater than one year	$ (63)	$ (198)
Securities available-for-sale agregate fair value of investment greater than one year	$ 4,093	$ 4,825
Number of securities held-to-maturity in one year or less | security	32	111
Securities held-to-maturity gross unrealized losses one year or less	$ 0	$ (14)
Securities held-to-maturity aggregate fair value of investment one year or less	$ 187	$ 769
Number of securities held-to-maturity greater than one year | security	386	491
Securities held-to-maturity gross unrealized losses greater than one year	$ (41)	$ (225)
Securities held-to-maturity aggregate fair value of investment greater than one year	$ 4,769	$ 7,372
Asset-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities available for sale in one year or less | security	0	1
Securities available-for-sale gross unrealized losses one year or less	$ 0	$ 0
Securities available-for-sale aggregate fair value of investment one year or less	$ 0	$ 0
Number of Securities available for sale greater than one year | security	5	4
Securities available-for-sale gross unrealized losses greater than one year	$ (3)	$ (2)
Securities available-for-sale agregate fair value of investment greater than one year	$ 36	$ 42
Foreign Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities available for sale in one year or less | security	18	16
Securities available-for-sale gross unrealized losses one year or less	$ 0	$ 0
Securities available-for-sale aggregate fair value of investment one year or less	$ 1,440	$ 1,724
Number of Securities available for sale greater than one year | security	0	0
Securities available-for-sale gross unrealized losses greater than one year	$ 0	$ 0
Securities available-for-sale agregate fair value of investment greater than one year	$ 0	$ 0
Obligations of U.S. states and political subdivision [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities held-to-maturity in one year or less | security	0	1
Securities held-to-maturity gross unrealized losses one year or less	$ 0	$ 0
Securities held-to-maturity aggregate fair value of investment one year or less	$ 0	$ 0
Number of securities held-to-maturity greater than one year | security	1	1
Securities held-to-maturity gross unrealized losses greater than one year	$ 0	$ 0
Securities held-to-maturity aggregate fair value of investment greater than one year	$ 0	$ 0

Securities - Realized gains and

Securities - Realized gains and losses on investment securities Transactions Attributable to available-for-sale securities (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 27	$ 21	$ 43	$ 30
Gross realized losses	(4)	(11)	(13)	(15)
Net realized gains	$ 23	$ 10	$ 30	$ 15

Securities - Distribution of ma

Securities - Distribution of maturities of debt securities with approximate yield of portfolio (Detail) $ in Millions	Jun. 30, 2019USD ($)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale amount within one year	$ 2,798
Available-for-sale yield within one year	1.27%
Available-for-sale amount after one but within five years	$ 10,428
Available-for-sale yield after one but within five years	2.03%
Available-for-sale amount after five but within ten years	$ 8,244
Available-for-sale yield after five but within ten years	2.26%
Available-for-sale amount after ten years	$ 15,852
Available-for-sale yield after ten years	2.81%
Total fair value within one year	$ 2,801
Total fair value after one but within five years	10,445
Total fair value after five but within ten years	8,191
Total fair value after ten years	15,817
Held-to-maturity amount within one year	$ 51
Held-to-maturity yield within one year	2.27%
Held-to-maturity amount after one but within five years	$ 394
Held-to-maturity yield after one but within five years	2.77%
Held-to-maturity after five but within ten years	$ 296
Held-to-maturity yield after five but within ten years	2.57%
Held-to-maturity after ten years	$ 13,186
Held-to-maturity yield after ten years	2.76%
Total fair value within one year	$ 51
Total fair value after one but within five years	399
Total fair value after five but within ten years	298
Total fair value after ten years	13,263
U.S. Treasury [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale amount within one year	$ 199
Available-for-sale yield within one year	2.22%
Available-for-sale amount after one but within five years	$ 7,760
Available-for-sale yield after one but within five years	1.81%
Available-for-sale amount after five but within ten years	$ 5,967
Available-for-sale yield after five but within ten years	2.05%
Available-for-sale amount after ten years	$ 3,016
Available-for-sale yield after ten years	2.80%
US Government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale amount within one year	$ 1,047
Available-for-sale yield within one year	2.99%
Available-for-sale amount after one but within five years	$ 1,168
Available-for-sale yield after one but within five years	2.83%
Available-for-sale amount after five but within ten years	$ 2,218
Available-for-sale yield after five but within ten years	2.74%
Available-for-sale amount after ten years	$ 3,779
Available-for-sale yield after ten years	3.00%
Held-to-maturity amount within one year	$ 50
Held-to-maturity yield within one year	2.22%
Held-to-maturity amount after one but within five years	$ 376
Held-to-maturity yield after one but within five years	2.72%
Held-to-maturity after five but within ten years	$ 269
Held-to-maturity yield after five but within ten years	2.45%
Held-to-maturity after ten years	$ 2,866
Held-to-maturity yield after ten years	3.04%
US Government agency issued or guaranteed [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale amount within one year	$ 0
Available-for-sale yield within one year	0.00%
Available-for-sale amount after one but within five years	$ 81
Available-for-sale yield after one but within five years	2.21%
Available-for-sale amount after five but within ten years	$ 1
Available-for-sale yield after five but within ten years	4.33%
Available-for-sale amount after ten years	$ 8,968
Available-for-sale yield after ten years	2.72%
Held-to-maturity amount within one year	$ 0
Held-to-maturity yield within one year	0.00%
Held-to-maturity amount after one but within five years	$ 13
Held-to-maturity yield after one but within five years	3.94%
Held-to-maturity after five but within ten years	$ 22
Held-to-maturity yield after five but within ten years	3.69%
Held-to-maturity after ten years	$ 10,318
Held-to-maturity yield after ten years	2.68%
Obligations of U.S. states and political subdivision [Member]
Debt Securities, Available-for-sale [Line Items]
Held-to-maturity amount within one year	$ 1
Held-to-maturity yield within one year	4.75%
Held-to-maturity amount after one but within five years	$ 5
Held-to-maturity yield after one but within five years	3.46%
Held-to-maturity after five but within ten years	$ 5
Held-to-maturity yield after five but within ten years	4.20%
Held-to-maturity after ten years	$ 0
Held-to-maturity yield after ten years	0.00%
Asset-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale amount within one year	$ 0
Available-for-sale yield within one year	0.00%
Available-for-sale amount after one but within five years	$ 0
Available-for-sale yield after one but within five years	0.00%
Available-for-sale amount after five but within ten years	$ 58
Available-for-sale yield after five but within ten years	5.21%
Available-for-sale amount after ten years	$ 89
Available-for-sale yield after ten years	3.90%
Held-to-maturity amount within one year	$ 0
Held-to-maturity yield within one year	0.00%
Held-to-maturity amount after one but within five years	$ 0
Held-to-maturity yield after one but within five years	0.00%
Held-to-maturity after five but within ten years	$ 0
Held-to-maturity yield after five but within ten years	0.00%
Held-to-maturity after ten years	$ 2
Held-to-maturity yield after ten years	7.83%
Foreign debt securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale amount within one year	$ 1,552
Available-for-sale yield within one year	0.00%
Available-for-sale amount after one but within five years	$ 1,419
Available-for-sale yield after one but within five years	2.56%
Available-for-sale amount after five but within ten years	$ 0
Available-for-sale yield after five but within ten years	0.00%
Available-for-sale amount after ten years	$ 0
Available-for-sale yield after ten years	0.00%

Securities - Additional Informa

Securities - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)security	Jun. 30, 2018USD ($)security	Jun. 30, 2019USD ($)security	Jun. 30, 2018USD ($)security	Dec. 31, 2018USD ($)
Debt Securities, Available-for-sale [Line Items]
Securities with changes to other than temporary impairment estimates related to credit component | security	0	0	0	0
Increase in credit losses for which an other-than-temporary impairment was previously recognized	$ 0	$ 0	$ 0	$ 0
Other assets [Member]
Debt Securities, Available-for-sale [Line Items]
Equity securities carried at fair value	302,000,000		302,000,000		$ 278,000,000
Equity securities without readily determinable fair values	9,000,000		9,000,000		7,000,000
Federal Home Loan Bank Stock	155,000,000		155,000,000		156,000,000
Federal Reserve Bank Stock	$ 559,000,000		$ 559,000,000		$ 631,000,000

Loans - Components of Loans (De

Loans - Components of Loans (Details) - USD ($) $ in Millions	Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 72,478		$ 68,978		$ 66,399
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	52,745		49,342
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	11,704		11,344		11,245
Commercial Loans [Member] | Business and Corporate Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	14,310		13,066		12,109
Commercial Loans [Member] | Global Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	20,896	[1]	20,167	[1]	18,877
Commercial Loans [Member] | Other Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	5,835	[2]	4,765	[2]	4,612
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	19,733		19,636
Consumer Loans [Member] | Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	17,421		17,383		17,326
Consumer Loans [Member] | Home Equity Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	911		982		1,086
Consumer Loans [Member] | Credit Cards [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,129		1,019		841
Consumer Loans [Member] | Other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	272		252		303
Affiliated Entity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 3,096		$ 2,274		$ 1,895
[1]	Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers.
[2]	Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018, respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.

Loans - Additional Information

Loans - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net deferred origination costs (fees)	$ 77,000,000		$ 77,000,000		$ 77,000,000
Net unamortized premium (discount)	1,000,000		1,000,000		$ 11,000,000
Commercial loans removed from TDR classification	12,000,000	$ 0	12,000,000	$ 0
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	0	0	0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	0	0	0
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	1,000,000	14,000,000	3,000,000	22,000,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 1,000,000	$ 1,000,000	$ 3,000,000	$ 4,000,000

Loans - Summary of Past Due Sta

Loans - Summary of Past Due Status of Loans (Detail) - USD ($) $ in Millions		Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		$ 719		$ 1,012
Current	[1]	71,759		67,966
Total loans		72,478		68,978		$ 66,399
Commercial Loans [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		40		211
Current	[1]	52,705		49,131
Total loans		52,745		49,342
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		11		79
Current	[1]	11,693		11,265
Total loans		11,704		11,344		11,245
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		29		117
Current	[1]	14,281		12,949
Total loans		14,310		13,066		12,109
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		0		0
Current	[1]	20,896		20,167
Total loans		20,896	[2]	20,167	[2]	18,877
Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		0		15
Current	[1]	5,835		4,750
Total loans		5,835	[3]	4,765	[3]	4,612
Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		679		801
Current	[1]	19,054		18,835
Total loans		19,733		19,636
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		598		723
Current	[1]	16,823		16,660
Total loans		17,421		17,383		17,326
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		37		41
Current	[1]	874		941
Total loans		911		982		1,086
Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		34		27
Current	[1]	1,095		992
Total loans		1,129		1,019		841
Consumer Loans [Member] | Other consumer [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		10		10
Current	[1]	262		242
Total loans		272		252		$ 303
Financing Receivables, 30 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		395		671
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial Loans [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		20		170
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		10		76
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		10		79
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		0		0
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		0		15
Financing Receivables, 30 to 89 Days Past Due [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		375		501
Financing Receivables, 30 to 89 Days Past Due [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		341		469
Financing Receivables, 30 to 89 Days Past Due [Member] | Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		12		14
Financing Receivables, 30 to 89 Days Past Due [Member] | Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		16		13
Financing Receivables, 30 to 89 Days Past Due [Member] | Consumer Loans [Member] | Other consumer [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		6		5
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		324		341
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loans [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		20		41
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		1		3
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		19		38
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		0		0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		0		0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		304		300
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		257		254
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		25		27
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		18		14
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loans [Member] | Other consumer [Member]
Financing Receivable, Past Due [Line Items]
Total Days Past Due, 30 Days or More		$ 4		$ 5
[1]	Loans less than 30 days past due are presented as current.
[2]	Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers.
[3]	Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018, respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.

Loans - Summary of Nonaccrual L

Loans - Summary of Nonaccrual Loans and Accruing Receivables 90 Days or More Delinquent (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Total nonaccruing loans		$ 591	$ 540
Total accruing loans contractually past due 90 days or more		23	21
Total nonperforming loans		614	561
Residential Mortgage Loan Nonaccrual Carried At Lower Of Amortized Cost Or Fair Value Less Cost To Sell		267	289
Commercial Loans [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		150	143
Total nonaccruing loans		172	143
Total accruing loans contractually past due 90 days or more		1	1
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		7	7
Total accruing loans contractually past due 90 days or more		0	0
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		90	70
Total accruing loans contractually past due 90 days or more		1	1
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		53	65
Total accruing loans contractually past due 90 days or more		0	0
Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		0	1
Total accruing loans contractually past due 90 days or more		0	0
Commercial Loans [Member] | Nonaccrual Loans Held-for-sale [Member]
Financing Receivable, Past Due [Line Items]
Total nonaccruing loans		22	0
Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		418	396
Total nonaccruing loans		419	397
Total accruing loans contractually past due 90 days or more		22	20
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	[1],[2],[3]	370	341
Total accruing loans contractually past due 90 days or more		0	0
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	[1],[3]	48	55
Total accruing loans contractually past due 90 days or more		0	0
Consumer Loans [Member] | Nonaccrual Loans Held-for-sale [Member]
Financing Receivable, Past Due [Line Items]
Total nonaccruing loans		1	1
Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		0	0
Total accruing loans contractually past due 90 days or more		18	14
Consumer Loans [Member] | Other consumer [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans		0	0
Total accruing loans contractually past due 90 days or more		$ 4	$ 6
[1]	At June 30, 2019 and December 31, 2018, nonaccrual consumer mortgage loans held for investment include $267 million and $289 million, respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell.
[2]	Nonaccrual consumer mortgage loans for all periods does not include guaranteed loans purchased from the Government National Mortgage Association. Repayment of these loans is predominantly insured by the Federal Housing Administration and as such, these loans have different risk characteristics from the rest of our consumer loan portfolio.
[3]	Nonaccrual consumer mortgage loans held for investment include all loans which are 90 or more days contractually delinquent as well as loans discharged under Chapter 7 bankruptcy and not re-affirmed and second lien loans where the first lien loan that we own or service is 90 or more days contractually delinquent.

Loans - Schedule of Additional

Loans - Schedule of Additional Information on Nonaccrual Loans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Receivables [Abstract]
Interest income that would have been recorded if the nonaccrual receivable had been current in accordance with contractual terms during the period	$ 7	$ 13	$ 16	$ 27
Interest income that was recorded on nonaccrual loans and included in interest income during the period	$ 3	$ 6	$ 6	$ 15

Loans - Summary of Receivables

Loans - Summary of Receivables which were Modified and as Result Became Classified as TDR Loans (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Loans which were modified and as a result became classified as TDR Loans	$ 0	$ 0	$ 0	$ 0
Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Loans which were modified and as a result became classified as TDR Loans	$ 1	$ 14	$ 3	$ 22
Weighted average rate of reduction	3.88%	1.58%	1.45%	2.02%
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Loans which were modified and as a result became classified as TDR Loans	$ 0	$ 12	$ 1	$ 17
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Loans which were modified and as a result became classified as TDR Loans	0	1	0	3
Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Loans which were modified and as a result became classified as TDR Loans	$ 1	$ 1	$ 2	$ 2

Loans - Summary of TDR and Rela

Loans - Summary of TDR and Related Credit Loss Reserves for TDR Loans (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[1],[2],[3]	$ 788	$ 859
Unpaid Principal Balance of TDR Loans	[1],[2],[3]	926	1,004
Allowance for credit losses on TDR Loans	[4]	16	17
Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3],[5]	143	181
Unpaid Principal Balance of TDR Loans	[2],[3],[5]	166	205
Allowance for credit losses on TDR Loans	[4]	12	12
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3]	59	68
Unpaid Principal Balance of TDR Loans	[2],[3]	74	86
Allowance for credit losses on TDR Loans	[4]	12	12
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3]	84	113
Unpaid Principal Balance of TDR Loans	[2],[3]	92	119
Allowance for credit losses on TDR Loans	[4]	0	0
Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3]	645	678
Unpaid Principal Balance of TDR Loans	[2],[3]	760	799
Allowance for credit losses on TDR Loans	[4]	4	5
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3],[6]	608	640
Unpaid Principal Balance of TDR Loans	[2],[3],[6]	694	730
Allowance for credit losses on TDR Loans	[4]	3	3
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3],[6]	33	35
Unpaid Principal Balance of TDR Loans	[2],[3],[6]	62	65
Allowance for credit losses on TDR Loans	[4]	0	1
Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Carrying Value of TDR Loans	[2],[3]	4	3
Unpaid Principal Balance of TDR Loans	[2],[3]	4	4
Allowance for credit losses on TDR Loans	[4]	$ 1	$ 1
[1]	At June 30, 2019 and December 31, 2018, the carrying value of TDR Loans includes $256 million and $286 million, respectively, of loans which are classified as nonaccrual.
[2]	TDR Loans are considered to be impaired loans. For commercial loans, impaired loans include other loans in addition to TDR Loans which totaled $63 million and $54 million at June 30, 2019 and December 31, 2018, respectively.
[3]	The carrying value of TDR Loans includes basis adjustments on the loans, such as partial charge-offs.
[4]	Included in the allowance for credit losses.
[5]	Additional commitments to lend to commercial borrowers whose loans have been modified in TDR Loans totaled $226 million and $151 million at June 30, 2019 and December 31, 2018, respectively.
[6]	At June 30, 2019 and December 31, 2018, the carrying value of consumer mortgage TDR Loans held for investment includes $584 million and $615 million, respectively, of loans that are recorded at the lower of amortized cost or fair value of the collateral less cost to sell.

Loans - Summary of TDR and Re_2

Loans - Summary of TDR and Related Credit Loss Reserves for TDR Loans - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other loans included in impaired loans apart from TDR loans	$ 63	$ 54
Residential mortgage loan TDR carried at lower of amortized cost or fair value less cost to sell	584	615	$ 635
Non Accrual loans included in TDR loan	256	286
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Additional commitments to lend to commercial borrowers with modified TDRs	$ 226	$ 151

Loans - Trouble Debt Restructur

Loans - Trouble Debt Restructuring Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	$ 799	$ 950	$ 817	$ 996
Interest income recognized on TDR loans	8	9	17	21
Commercial Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	147	247	158	288
Interest income recognized on TDR loans	1	1	3	6
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	65	137	66	156
Interest income recognized on TDR loans	1	0	2	4
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	82	110	92	132
Interest income recognized on TDR loans	0	1	1	2
Consumer Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	652	703	659	708
Interest income recognized on TDR loans	7	8	14	15
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	615	664	621	670
Interest income recognized on TDR loans	6	7	13	14
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	33	35	34	34
Interest income recognized on TDR loans	1	1	1	1
Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Average balance of TDR loans	$ 4	$ 4	$ 4	$ 4

Loans - Loans Classified as TDR

Loans - Loans Classified as TDR Loans (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Commercial Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans which were classified as TDR loans during previous 12 months which became contractually delinquent	$ 0	$ 0	$ 0	$ 0
Threshold period for troubled debt restructuring status	90 days	90 days	90 days	90 days
Consumer Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans which were classified as TDR loans during previous 12 months which became contractually delinquent	$ 1	$ 1	$ 3	$ 4
Threshold period for troubled debt restructuring status	60 days	60 days	60 days	60 days
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans which were classified as TDR loans during previous 12 months which became contractually delinquent	$ 1	$ 0	$ 3	$ 2
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans which were classified as TDR loans during previous 12 months which became contractually delinquent	$ 0	$ 1	$ 0	$ 2

Loans - Impaired Commercial Loa

Loans - Impaired Commercial Loans Considered as TDR Loans (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
TDR Loans	[1],[2],[3]	$ 788	$ 859
Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	[4]	49	61
Amount without Impairment Reserves	[4]	157	174
Total Impaired Commercial Loans	[4],[5]	206	235
Impairment Reserve		23	19
Unpaid principal balance of impaired commercial loans		225	256
TDR Loans	[2],[3],[6]	143	181
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	[4]	3	3
Amount without Impairment Reserves	[4]	1	3
Total Impaired Commercial Loans	[4],[5]	4	6
Impairment Reserve		2	1
Unpaid principal balance of impaired commercial loans		4	6
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	[4]	46	58
Amount without Impairment Reserves	[4]	55	37
Total Impaired Commercial Loans	[4],[5]	101	95
Impairment Reserve		21	18
Unpaid principal balance of impaired commercial loans		110	109
TDR Loans	[2],[3]	59	68
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	[4]	0	0
Amount without Impairment Reserves	[4]	101	133
Total Impaired Commercial Loans	[4],[5]	101	133
Impairment Reserve		0	0
Unpaid principal balance of impaired commercial loans		111	140
TDR Loans	[2],[3]	$ 84	113
Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	[4]		0
Amount without Impairment Reserves	[4]		1
Total Impaired Commercial Loans	[4],[5]		1
Impairment Reserve			0
Unpaid principal balance of impaired commercial loans			$ 1
[1]	At June 30, 2019 and December 31, 2018, the carrying value of TDR Loans includes $256 million and $286 million, respectively, of loans which are classified as nonaccrual.
[2]	TDR Loans are considered to be impaired loans. For commercial loans, impaired loans include other loans in addition to TDR Loans which totaled $63 million and $54 million at June 30, 2019 and December 31, 2018, respectively.
[3]	The carrying value of TDR Loans includes basis adjustments on the loans, such as partial charge-offs.
[4]	Reflects the carrying value of impaired commercial loans and includes basis adjustments on the loans, such as partial charge-offs.
[5]	Includes impaired commercial loans that are also considered TDR Loans which totaled $143 million and $181 million at June 30, 2019 and December 31, 2018, respectively.
[6]	Additional commitments to lend to commercial borrowers whose loans have been modified in TDR Loans totaled $226 million and $151 million at June 30, 2019 and December 31, 2018, respectively.

Loans - Average Balance and Int

Loans - Average Balance and Interest Income Recognized on Impaired Commercial Loans (Detail) - Commercial Loans [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Impaired [Line Items]
Total average balance of impaired commercial loans	$ 209	$ 532	$ 217	$ 586
Total interest income recognized on impaired commercial loans	2	2	4	8
Real Estate, Including Construction [Member]
Financing Receivable, Impaired [Line Items]
Total average balance of impaired commercial loans	4	12	5	11
Business and Corporate Banking [Member]
Financing Receivable, Impaired [Line Items]
Total average balance of impaired commercial loans	105	272	101	264
Total interest income recognized on impaired commercial loans	2	1	3	6
Global Banking [Member]
Financing Receivable, Impaired [Line Items]
Total average balance of impaired commercial loans	100	248	111	311
Total interest income recognized on impaired commercial loans	$ 0	$ 1	$ 1	$ 2

Loans - Summary of Criticized A

Loans - Summary of Criticized Assets for Commercial Loans (Detail) - USD ($) $ in Millions	Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 72,478		$ 68,978		$ 66,399
Commercial Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	52,745		49,342
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	11,704		11,344		11,245
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	14,310		13,066		12,109
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	20,896	[1]	20,167	[1]	18,877
Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,835	[2]	4,765	[2]	$ 4,612
Commercial Loans [Member] | Criticized [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	2,205		1,611
Commercial Loans [Member] | Criticized [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	936		549
Commercial Loans [Member] | Criticized [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	750		522
Commercial Loans [Member] | Criticized [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	519		539
Commercial Loans [Member] | Criticized [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			1
Commercial Loans [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,309		907
Commercial Loans [Member] | Special Mention [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	784		452
Commercial Loans [Member] | Special Mention [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	282		193
Commercial Loans [Member] | Special Mention [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	243		262
Commercial Loans [Member] | Special Mention [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			0
Commercial Loans [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	868		685
Commercial Loans [Member] | Substandard [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	151		93
Commercial Loans [Member] | Substandard [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	441		314
Commercial Loans [Member] | Substandard [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	276		277
Commercial Loans [Member] | Substandard [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			1
Commercial Loans [Member] | Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	28		19
Commercial Loans [Member] | Doubtful [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1		4
Commercial Loans [Member] | Doubtful [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	27		15
Commercial Loans [Member] | Doubtful [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 0		0
Commercial Loans [Member] | Doubtful [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			$ 0
[1]	Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers.
[2]	Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018, respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.

Loans - Status of Commercial Lo

Loans - Status of Commercial Loan Portfolio (Detail) - USD ($) $ in Millions	Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Accruing Loans Contractually Past Due 90 days or More	$ 23		$ 21
Total loans	72,478		68,978		$ 66,399
Commercial Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans	52,594		49,198
Nonaccrual Loans	150		143
Accruing Loans Contractually Past Due 90 days or More	1		1
Total loans	52,745		49,342
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans	11,697		11,337
Nonaccrual Loans	7		7
Accruing Loans Contractually Past Due 90 days or More	0		0
Total loans	11,704		11,344		11,245
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans	14,219		12,995
Nonaccrual Loans	90		70
Accruing Loans Contractually Past Due 90 days or More	1		1
Total loans	14,310		13,066		12,109
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans	20,843		20,102
Nonaccrual Loans	53		65
Accruing Loans Contractually Past Due 90 days or More	0		0
Total loans	20,896	[1]	20,167	[1]	18,877
Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans	5,835		4,764
Nonaccrual Loans	0		1
Accruing Loans Contractually Past Due 90 days or More	0		0
Total loans	$ 5,835	[2]	$ 4,765	[2]	$ 4,612
[1]	Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers.
[2]	Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018, respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.

Loans - Credit Risk Profile of

Loans - Credit Risk Profile of Commercial Loans (Detail) - USD ($) $ in Millions		Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		$ 72,478		$ 68,978		$ 66,399
Commercial Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		52,745		49,342
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		11,704		11,344		11,245
Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		14,310		13,066		12,109
Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		20,896	[1]	20,167	[1]	18,877
Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		5,835	[2]	4,765	[2]	$ 4,612
Investment Grade [Member] | Commercial Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	32,794		31,197
Investment Grade [Member] | Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	6,807		6,769
Investment Grade [Member] | Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	5,969		5,674
Investment Grade [Member] | Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	14,860		14,764
Investment Grade [Member] | Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	5,158		3,990
Noninvestment Grade [Member] | Commercial Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		19,951		18,145
Noninvestment Grade [Member] | Commercial Loans [Member] | Real Estate, Including Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		4,897		4,575
Noninvestment Grade [Member] | Commercial Loans [Member] | Business and Corporate Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		8,341		7,392
Noninvestment Grade [Member] | Commercial Loans [Member] | Global Banking [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		6,036		5,403
Noninvestment Grade [Member] | Commercial Loans [Member] | Other Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		$ 677		$ 775
[1]	Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers.
[2]	Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018, respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.
[3]	Investment grade includes commercial loans with credit ratings of at least BBB- or above or the equivalent based on our internal credit rating system.

Loans - Delinquency Ratio for C

Loans - Delinquency Ratio for Consumer Loan (Detail) - Consumer Loans [Member] - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Delinquent Loans		$ 377	$ 405
Delinquency Ratio		1.91%	2.05%
Residential Mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Delinquent Loans	[1],[2]	$ 319	$ 347
Delinquency Ratio	[1],[2]	1.83%	1.99%
Home Equity Mortgages [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Delinquent Loans	[1],[2]	$ 27	$ 30
Delinquency Ratio	[1],[2]	2.96%	3.05%
Credit Cards [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Delinquent Loans		$ 25	$ 20
Delinquency Ratio		2.21%	1.96%
Other consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Delinquent Loans		$ 6	$ 8
Delinquency Ratio		2.21%	2.62%
[1]	At June 30, 2019 and December 31, 2018, consumer mortgage loan delinquency includes $239 million and $254 million, respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell, including $1 million and $1 million, respectively, relating to loans held for sale.
[2]	At June 30, 2019 and December 31, 2018, consumer mortgage loans and loans held for sale include $146 million and $125 million, respectively, of loans that were in the process of foreclosure.

Loans - Delinquency Ratio for_2

Loans - Delinquency Ratio for Consumer Loan - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Residential Mortgage Loan Delinquency Carried At Lower Of Amortized Cost Or Fair Value Less Cost To Sell	$ 239	$ 254
Residential Mortgage Loan Delinquency Carried At Lower Of Amortized Cost Or Fair Value Less Cost To Sell, Held-for-Sale	1	1
Consumer Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 146	$ 125

Loans - Status of Consumer Loan

Loans - Status of Consumer Loan Portfolio (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Accruing Loans Contractually Past Due 90 days or More		$ 23	$ 21
Total loans		72,478	68,978	$ 66,399
Consumer Loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans		19,293	19,220
Nonaccrual Loans		418	396
Accruing Loans Contractually Past Due 90 days or More		22	20
Total loans		19,733	19,636
Consumer Loans [Member] | Residential Mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans		17,051	17,042
Nonaccrual Loans	[1],[2],[3]	370	341
Accruing Loans Contractually Past Due 90 days or More		0	0
Total loans		17,421	17,383	17,326
Consumer Loans [Member] | Home Equity Mortgages [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans		863	927
Nonaccrual Loans	[1],[3]	48	55
Accruing Loans Contractually Past Due 90 days or More		0	0
Total loans		911	982	1,086
Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans		1,111	1,005
Nonaccrual Loans		0	0
Accruing Loans Contractually Past Due 90 days or More		18	14
Total loans		1,129	1,019	841
Consumer Loans [Member] | Other consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Performing Loans		268	246
Nonaccrual Loans		0	0
Accruing Loans Contractually Past Due 90 days or More		4	6
Total loans		$ 272	$ 252	$ 303
[1]	At June 30, 2019 and December 31, 2018, nonaccrual consumer mortgage loans held for investment include $267 million and $289 million, respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell.
[2]	Nonaccrual consumer mortgage loans for all periods does not include guaranteed loans purchased from the Government National Mortgage Association. Repayment of these loans is predominantly insured by the Federal Housing Administration and as such, these loans have different risk characteristics from the rest of our consumer loan portfolio.
[3]	Nonaccrual consumer mortgage loans held for investment include all loans which are 90 or more days contractually delinquent as well as loans discharged under Chapter 7 bankruptcy and not re-affirmed and second lien loans where the first lien loan that we own or service is 90 or more days contractually delinquent.

Loans - Concentration of Credit

Loans - Concentration of Credit Risk (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Interest only residential mortgage loans	$ 3,254	$ 3,208

Allowance for Credit Losses - S

Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses and Related Loan Balance by Product (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		$ 583	$ 599	$ 541	$ 681
Provision charged (credited) to income		46	(45)	104	(116)
Charge offs		(23)	(50)	(44)	(91)
Recoveries		7	27	12	57
Net (charge offs) recoveries		(16)	(23)	(32)	(34)
Balance at end of period		613	531	613	531
Ending balance: collectively evaluated for impairment						$ 586				$ 481
Ending balance: individually evaluated for impairment						27				50
Total allowances for credit losses		583	599	541	681	613		$ 541		531
Collectively evaluated for impairment	[1]					71,349				64,958
Individually evaluated for impairment	[2]					267				507
Loans carried at the lower of amortized cost or fair value less cost to sell						862				934
Total loans						72,478		68,978		66,399
Commercial Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Total loans						52,745		49,342
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		119	92	116	82
Provision charged (credited) to income		30	(4)	33	6
Charge offs		0	0	0	0
Recoveries		0	0	0	0
Net (charge offs) recoveries		0	0	0	0
Balance at end of period		149	88	149	88
Ending balance: collectively evaluated for impairment						147				87
Ending balance: individually evaluated for impairment						2				1
Total allowances for credit losses		119	92	116	82	149		116		88
Collectively evaluated for impairment	[1]					11,700				11,234
Individually evaluated for impairment	[2]					4				11
Loans carried at the lower of amortized cost or fair value less cost to sell						0				0
Total loans						11,704		11,344		11,245
Commercial Loans [Member] | Business and Corporate Banking [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		239	207	219	244
Provision charged (credited) to income		13	(27)	35	(61)
Charge offs		(2)	(6)	(4)	(31)
Recoveries		1	22	1	44
Net (charge offs) recoveries		(1)	16	(3)	13
Balance at end of period		251	196	251	196
Ending balance: collectively evaluated for impairment						230				169
Ending balance: individually evaluated for impairment						21				27
Total allowances for credit losses		239	207	219	244	251		219		196
Collectively evaluated for impairment	[1]					14,209				11,852
Individually evaluated for impairment	[2]					101				257
Loans carried at the lower of amortized cost or fair value less cost to sell						0				0
Total loans						14,310		13,066		12,109
Commercial Loans [Member] | Global Banking [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		122	211	108	264
Provision charged (credited) to income		(9)	(25)	5	(74)
Charge offs		(3)	(32)	(3)	(37)
Recoveries		0	0	0	1
Net (charge offs) recoveries		(3)	(32)	(3)	(36)
Balance at end of period		110	154	110	154
Ending balance: collectively evaluated for impairment						110				139
Ending balance: individually evaluated for impairment						0				15
Total allowances for credit losses		122	211	108	264	110		108		154
Collectively evaluated for impairment	[1]					20,795				18,704
Individually evaluated for impairment	[2]					101				173
Loans carried at the lower of amortized cost or fair value less cost to sell						0				0
Total loans						20,896	[3]	20,167	[3]	18,877
Commercial Loans [Member] | Other Commercial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		15	19	15	18
Provision charged (credited) to income		(6)	0	(6)	1
Charge offs		0	0	0	0
Recoveries		0	0	0	0
Net (charge offs) recoveries		0	0	0	0
Balance at end of period		9	19	9	19
Ending balance: collectively evaluated for impairment						9				19
Ending balance: individually evaluated for impairment						0				0
Total allowances for credit losses		15	19	15	18	9		15		19
Collectively evaluated for impairment	[1]					5,835				4,612
Individually evaluated for impairment	[2]					0				0
Loans carried at the lower of amortized cost or fair value less cost to sell						0				0
Total loans						5,835	[4]	4,765	[4]	4,612
Consumer Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Total loans						19,733		19,636
Consumer Loans [Member] | Residential Mortgages [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		10	18	13	25
Provision charged (credited) to income		1	(4)	0	(14)
Charge offs		(3)	(1)	(7)	(1)
Recoveries		3	2	5	5
Net (charge offs) recoveries		0	1	(2)	4
Balance at end of period		11	15	11	15
Ending balance: collectively evaluated for impairment						8				10
Ending balance: individually evaluated for impairment						3				5
Total allowances for credit losses		10	18	13	25	11		13		15
Collectively evaluated for impairment	[1]					16,559				16,397
Individually evaluated for impairment	[2]					53				59
Loans carried at the lower of amortized cost or fair value less cost to sell						809				870
Total loans						17,421		17,383		17,326
Consumer Loans [Member] | Home Equity Mortgages [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		8	10	7	11
Provision charged (credited) to income		(1)	0	0	(1)
Charge offs		(1)	(2)	(2)	(4)
Recoveries		1	1	2	3
Net (charge offs) recoveries		0	(1)	0	(1)
Balance at end of period		7	9	7	9
Ending balance: collectively evaluated for impairment						7				8
Ending balance: individually evaluated for impairment						0				1
Total allowances for credit losses		8	10	7	11	7		7		9
Collectively evaluated for impairment	[1]					854				1,019
Individually evaluated for impairment	[2]					4				3
Loans carried at the lower of amortized cost or fair value less cost to sell						53				64
Total loans						911		982		1,086
Consumer Loans [Member] | Credit Cards [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		63	38	58	32
Provision charged (credited) to income		19	13	35	25
Charge offs		(12)	(7)	(25)	(15)
Recoveries		1	1	3	3
Net (charge offs) recoveries		(11)	(6)	(22)	(12)
Balance at end of period		71	45	71	45
Ending balance: collectively evaluated for impairment						70				44
Ending balance: individually evaluated for impairment						1				1
Total allowances for credit losses		63	38	58	32	71		58		45
Collectively evaluated for impairment	[1]					1,125				837
Individually evaluated for impairment	[2]					4				4
Loans carried at the lower of amortized cost or fair value less cost to sell						0				0
Total loans						1,129		1,019		841
Consumer Loans [Member] | Other consumer [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		7	4	5	5
Provision charged (credited) to income		(1)	2	2	2
Charge offs		(2)	(2)	(3)	(3)
Recoveries		1	1	1	1
Net (charge offs) recoveries		(1)	(1)	(2)	(2)
Balance at end of period		5	5	5	5
Ending balance: collectively evaluated for impairment						5				5
Ending balance: individually evaluated for impairment						0				0
Total allowances for credit losses		$ 7	$ 4	$ 5	$ 5	5		5		5
Collectively evaluated for impairment	[1]					272				303
Individually evaluated for impairment	[2]					0				0
Loans carried at the lower of amortized cost or fair value less cost to sell						0				0
Total loans						$ 272		$ 252		$ 303
[1]	Other commercial includes loans to HSBC affiliates totaling $3,096 million and $1,895 million at June 30, 2019 and 2018, respectively, for which we do not carry an associated allowance for credit losses
[2]	For consumer loans and certain small business loans, these amounts represent TDR Loans for which we evaluate reserves using a discounted cash flow methodology. Each loan is individually identified as a TDR Loan and then grouped together with other TDR Loans with similar characteristics. The discounted cash flow analysis is then applied to these groups of TDR Loans. Loans individually evaluated for impairment exclude TDR Loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell which totaled $584 million and $635 million at June 30, 2019 and 2018, respectively.
[3]	Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking clients managed by HSBC on a global basis and complex large business clients supported by Global Banking and Markets relationship managers.
[4]	Includes loans to HSBC affiliates which totaled $3,096 million and $2,274 million at June 30, 2019 and December 31, 2018, respectively. See Note 14, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.

Allowance for Credit Losses -_2

Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses and Related Loan Balance by Product - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 72,478	$ 68,978	$ 66,399
TDR loans carried at lower of amortized cost or fair value less cost to sell	584	615	635
Affiliated Entity [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 3,096	$ 2,274	$ 1,895

Loans Held for Sale (Details)

Loans Held for Sale (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	$ 191	$ 512
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	151	394
Commercial Loans [Member] | Real Estate, Including Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	66	27
Commercial Loans [Member] | Global Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	85	367
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	40	118
Consumer Loans [Member] | Residential Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	40	65
Consumer Loans [Member] | Other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	$ 0	$ 53

Loans Held for Sale - Additiona

Loans Held for Sale - Additional Information (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	$ 191,000,000			$ 191,000,000		$ 512,000,000
Revenue associated with the economic hedging program (less than)	497,000,000		$ 105,000,000	1,549,000,000	$ (402,000,000)
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	151,000,000			151,000,000		394,000,000
Valuation allowance	1,000,000			1,000,000		3,000,000
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	40,000,000			40,000,000		118,000,000
Valuation allowance	2,000,000			2,000,000		4,000,000
Commercial Loans - Fair Value Option [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	128,000,000			128,000,000		109,000,000
Commercial Loans - Transferred to Held for Sale [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	23,000,000			23,000,000		$ 285,000,000
Student Loans [Member] | Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of loans held-for-sale to loans held for investment		$ 53,000,000
Other Income (Loss) [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lower of amortized cost or fair value adjustment	0		(1,000,000)	0	(3,000,000)
Residential mortgage banking revenue (expense) [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revenue associated with the economic hedging program (less than)	$ 1,000,000		$ 1,000,000	$ 2,000,000	$ 1,000,000

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 1,607	$ 1,607	$ 1,607
Accumulated impairment loss	$ 670	$ 670

Leases - Components of Operatin

Leases - Components of Operating Lease Costs (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Leases [Abstract]
Operating lease cost	$ 34	$ 66
Variable lease cost	17	31
Short-term lease cost	2	6
Sublease income	(14)	(28)
Total operating lease costs, net	39	75
Cash paid for amounts included in the measurement of operating lease liabilities	31	62
ROU assets recognized for new operating lease liabilities	$ 0	$ 10

Leases - Operating ROU Assets a

Leases - Operating ROU Assets and Liabilities (Details) $ in Millions	Jun. 30, 2019USD ($)
Leases [Abstract]
Operating lease ROU assets	$ 735	[1]
Operating lease liabilities	$ 786
Weighted-average remaining lease term	7 years 3 months
Weighted-average discount rate (percent)	3.20%
[1]	Reported net of level lease adjustments and exit cost obligations.

Leases - Maturity Analysis of O

Leases - Maturity Analysis of Operating Lease Liabilities (Details) $ in Millions	Jun. 30, 2019USD ($)
Maturity of Operating Lease Liabilities
2019	$ 56
2020	135
2021	135
2022	131
2023	130
Thereafter	312
Total future operating lease payments	899
Less - imputed interest	(113)
Total operating lease liabilities	$ 786

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2019
Leases [Abstract]
Additional operating leases that have not yet commenced			$ 24
Net rental expense	$ 24	$ 47

Leases Leases - Schedule of Fut

Leases Leases - Schedule of Future Minimum Rental Payments for Operating Leases (Details) $ in Millions	Dec. 31, 2018USD ($)
Minimum Lease Payments
2019	$ 136
2020	125
2021	115
2022	103
2023	91
Thereafter	182
Net minimum lease commitments	752
Minimum Sublease Income
2019	(58)
2020	(2)
2021	(1)
2022	0
2023	0
Thereafter	(1)
Net minimum lease commitments	(62)
Net
2019	78
2020	123
2021	114
2022	103
2023	91
Thereafter	181
Net minimum lease commitments	$ 690

Derivative Financial Instrume_3

Derivative Financial Instruments - Fair Value of Derivatives and Balance Offsetting (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Assets		$ 31,190	$ 30,330
Derivative Liabilities		31,463	31,671
Netting assets	[1],[2]	24,555	25,172
Netting liabilities	[1],[2]	24,555	25,172
Less: Gross amounts of cash collateral received subject to enforceable master netting agreements(5)(6)	[1],[3]	3,439	2,020
Less: Gross amounts of cash collateral posted subject to enforceable master netting agreements(5)(6)	[1],[3]	3,627	3,675
Derivative Asset		3,196	3,138
Derivative Liability		3,281	2,824
Less: Gross amounts of financial instrument collateral received not offset		789	832
Less: Gross amounts of financial instrument collateral posted not offset		1,572	568
Net amount of derivative asset		2,407	2,306
Net amount of derivative liability		1,709	2,256
Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Less: Gross amounts of cash collateral received subject to enforceable master netting agreements(5)(6)		2,638	2,013
Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Less: Gross amounts of cash collateral posted subject to enforceable master netting agreements(5)(6)		3,627	3,458
Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4]	8	17
Designated as Hedging Instrument [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4]	215	162
Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5]	11,353	9,918
Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5]	12,545	10,839
Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5]	13,361	15,897
Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5]	13,021	15,699
Equity contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets		2,754	2,034
Equity contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities		2,744	2,061
Precious metals contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5]	1,360	845
Precious metals contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5]	1,391	900
Credit contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5]	1,118	950
Credit contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5]	1,247	938
Fair Value Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4]	0	6
Fair Value Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4]	161	117
OTC Cleared [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	51	50
OTC Cleared [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	18	14
OTC Cleared [Member] | Credit contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	191	125
OTC Cleared [Member] | Credit contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	178	107
OTC Cleared [Member] | Fair Value Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6]	0	6
OTC Cleared [Member] | Fair Value Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6]	0	0
Bilateral OTC [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	11,204	9,866
Bilateral OTC [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	12,504	10,780
Bilateral OTC [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4]	207	133
Bilateral OTC [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4]	67	216
Bilateral OTC [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	13,360	15,897
Bilateral OTC [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	12,993	15,684
Bilateral OTC [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6]	1	13
Bilateral OTC [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6]	8	2
Bilateral OTC [Member] | Equity contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	2,738	2,034
Bilateral OTC [Member] | Equity contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	2,744	2,061
Bilateral OTC [Member] | Equity contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6]	1,022	512
Bilateral OTC [Member] | Equity contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6]	157	805
Bilateral OTC [Member] | Precious metals contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	1,254	829
Bilateral OTC [Member] | Precious metals contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	1,255	626
Bilateral OTC [Member] | Credit contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	927	825
Bilateral OTC [Member] | Credit contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	1,069	831
Bilateral OTC [Member] | Credit contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6]	1	6
Bilateral OTC [Member] | Credit contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6]	28	9
Bilateral OTC [Member] | Other Contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6],[7]	5	5
Bilateral OTC [Member] | Other Contracts [Member] | Not Designated as Hedging Instrument, Other [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6],[7]	40	40
Bilateral OTC [Member] | Fair Value Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6]	0	0
Bilateral OTC [Member] | Fair Value Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6]	161	117
Bilateral OTC [Member] | Cash Flow Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4]	0	0
Bilateral OTC [Member] | Cash Flow Hedging [Member] | Interest rate contracts [Member] | Designated as Hedging Instrument [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4]	31	13
Bilateral OTC [Member] | Cash Flow Hedging [Member] | Foreign exchange contracts [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[4],[6]	8	11
Bilateral OTC [Member] | Cash Flow Hedging [Member] | Foreign exchange contracts [Member] | Designated as Hedging Instrument [Member] | Interest taxes and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[4],[6]	23	32
Exchange Traded [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	98	2
Exchange Traded [Member] | Interest rate contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	23	45
Exchange Traded [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	1	0
Exchange Traded [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	28	15
Exchange Traded [Member] | Equity contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	16	0
Exchange Traded [Member] | Equity contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	0	0
Exchange Traded [Member] | Precious metals contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	[5],[6]	106	16
Exchange Traded [Member] | Precious metals contracts [Member] | Not Designated as Hedging Instrument, Trading [Member] | Trading Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[5],[6]	$ 136	$ 274
[1]	Netting is performed at a counterparty level in cases where enforceable master netting agreements are in place, regardless of the type of derivative instrument. Therefore, we have not allocated netting to the different types of derivative instruments shown in the table above.
[2]	Represents the netting of derivative receivable and payable balances for the same counterparty under enforceable netting agreements.
[3]	Represents the netting of cash collateral posted and received by counterparty under enforceable netting agreements.
[4]	Derivative assets / liabilities related to cash flow hedges, fair value hedges and derivative instruments held for purposes other than for trading are recorded in other assets / interest, taxes and other liabilities on the consolidated balance sheet.
[5]	Trading related derivative assets / liabilities are recorded in trading assets / trading liabilities on the consolidated balance sheet.
[6]	Over-the-counter ("OTC") derivatives include derivatives executed and settled bilaterally with counterparties without the use of an organized exchange or central clearing house. The credit risk associated with bilateral OTC derivatives is managed through obtaining collateral and enforceable master netting agreements. OTC-cleared derivatives are executed bilaterally in the OTC market but then novated to a central clearing counterparty, whereby the central clearing counterparty becomes the counterparty to each of the original counterparties. Exchange traded derivatives are executed directly on an organized exchange. Credit risk is minimized for OTC-cleared derivatives and exchange traded derivatives through daily margining requirements. In addition, OTC-cleared interest-rate derivatives with certain central clearing counterparties are settled daily.
[7]	Consists of swap agreements entered into in conjunction with the sales of Visa Inc. ("Visa") Class B common shares ("Class B Shares").

Derivative Financial Instrume_4

Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Derivative [Line Items]
Losses related to discontinued cash flow hedge relationships amortized to earnings	$ 9	$ 5	$ 19	$ 9
Next twelve months, reclassification of remaining losses to earnings resulting from cash flow hedges			31
Aggregate fair value of all derivative instruments with credit-risk related contingent features	622		622		$ 979
Collateral already posted aggregate fair value	$ 304		$ 304		$ 422

Derivative Financial Instrume_5

Derivative Financial Instruments Derivative Financial Instruments - Carrying Value of Hedged Items in Fair Value Hedge (Details) $ in Millions	Jun. 30, 2019USD ($)
Securities available-for-sale [Member]
Derivatives, Fair Value [Line Items]
Carrying amount of hedged asset items	$ 11,745
Active hedged asset adjustments	716
Discontinued hedged asset adjustments	252
Total hedged asset adjustments	968
Long-term Debt [Member]
Derivatives, Fair Value [Line Items]
Carrying amount of hedged liability items	11,964
Active hedged liability adjustments	294
Discontinued hedged liability adjustments	(52)
Total hedged liability adjustments	$ 242

Derivative Financial Instrume_6

Derivative Financial Instruments - Gains and Losses on Hedged Items in Fair Value Hedges (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest Income Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative	$ (251)	$ (24)	$ (424)	$ (53)
Gain (Loss) on Hedged Items	198	36	349	66
Other Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative	0	118	0	420
Gain (Loss) on Hedged Items	0	(113)	0	(409)
Net Ineffective Gain (Loss) Recognized - Other Income	0	5	0	11
Securities available-for-sale [Member] | Interest Income [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative	(404)	(10)	(661)	(33)
Gain (Loss) on Hedged Items	488	89	838	176
Securities available-for-sale [Member] | Other Income (Loss) [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative	0	125	0	487
Gain (Loss) on Hedged Items	0	(117)	0	(474)
Net Ineffective Gain (Loss) Recognized - Other Income	0	8	0	13
Long-term Debt [Member] | Interest Expense [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative	153	(14)	237	(20)
Gain (Loss) on Hedged Items	(290)	(53)	(489)	(110)
Long-term Debt [Member] | Other Income (Loss) [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative	0	(7)	0	(67)
Gain (Loss) on Hedged Items	0	4	0	65
Net Ineffective Gain (Loss) Recognized - Other Income	$ 0	$ (3)	$ 0	$ (2)

Derivative Financial Instrume_7

Derivative Financial Instruments - Gains and Losses on Derivative Instruments Designated and Qualifying As Hedging Instruments in Cash Flow Hedges (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives(1)	[1]	$ (2)		$ 6
Gain (Loss) Recognized in AOCI on Derivatives(1)	[1]		$ 8		$ 6
Gain (Loss) Reclassified From AOCI into Income(1)	[1]	(9)		(19)
Gain (Loss) Reclassified From AOCI into Income(1)	[1]		(5)		(9)
Foreign exchange contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives(1)	[1]	0		1
Gain (Loss) Recognized in AOCI on Derivatives(1)	[1]		(1)		(6)
Foreign exchange contracts [Member] | Interest Income Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified From AOCI into Income(1)	[1]	0		0
Gain (Loss) Reclassified From AOCI into Income(1)	[1]		0		0
Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives(1)	[1]	(2)		5
Gain (Loss) Recognized in AOCI on Derivatives(1)	[1]		9		12
Interest rate contracts [Member] | Interest Income Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified From AOCI into Income(1)	[1]	$ (9)		$ (19)
Gain (Loss) Reclassified From AOCI into Income(1)	[1]		$ (5)		$ (9)
[1]	As a result of adopting new accounting guidance discussed in Note 21, "New Accounting Pronouncements," beginning January 1, 2019, gains and losses on the derivatives in cash flow hedges are initially reported in AOCI and then reclassified into earnings in the same accounting period in which the designated forecasted transaction or hedged item affects earnings. Prior to January 1, 2019, cash flow hedge ineffectiveness was separately measured and reported immediately in other income (loss). Cash flow hedge ineffectiveness was immaterial during the three and six months ended June 30, 2018.

Derivative Financial Instrume_8

Derivative Financial Instruments - Gains and Losses on Derivative Instruments Held For Trading Purpose (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for trading purposes	$ (88)	$ 240	$ (240)	$ 467
Trading revenue [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for trading purposes	(171)	126	(115)	329
Trading revenue [Member] | Foreign exchange contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for trading purposes	677	28	814	(72)
Trading revenue [Member] | Equity contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for trading purposes	(61)	2	(150)	(1)
Trading revenue [Member] | Precious metals contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for trading purposes	(388)	85	(522)	215
Trading revenue [Member] | Credit contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for trading purposes	$ (145)	$ (1)	$ (267)	$ (4)

Derivative Financial Instrume_9

Derivative Financial Instruments - Gains and Losses on Derivative Instruments Held For Other Purpose (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	$ 497	$ 105	$ 1,549		$ (402)
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	496	94	1,555		(422)
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Interest rate contracts [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	180	(54)	336		(216)
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Foreign exchange contracts [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	1	(8)	0		(10)
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Equity contracts [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	324	167	1,238		(172)
Other Income (Loss) [Member] | Interest rate contracts [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	(1)	0	(2)		0
Other Income (Loss) [Member] | Credit contracts [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	(4)	12	(14)		10
Other Income (Loss) [Member] | Other Contracts [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivatives held for other purposes	$ (3)	$ (12)	$ (9)	[1]	$ (14)	[1]
[1]	Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares.

Derivative Financial Instrum_10

Derivative Financial Instruments - Credit-Risk Related Contingent Features (Detail) $ in Millions	Jun. 30, 2019USD ($)
One-notch Downgrade [Member]
Derivative [Line Items]
Amount of additional collateral to be posted upon downgrade	$ 34
Two-notch Downgrade [Member]
Derivative [Line Items]
Amount of additional collateral to be posted upon downgrade	$ 55

Derivative Financial Instrum_11

Derivative Financial Instruments - Notional Value of Derivative Contracts (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Derivative [Line Items]
Total		$ 5,516,710	$ 5,556,668
Interest rate contracts [Member]
Derivative [Line Items]
Total		3,933,161	4,203,667
Interest Rate Futures and Forwards [Member]
Derivative [Line Items]
Total		653,615	787,049
Interest Rate Swap [Member]
Derivative [Line Items]
Total		3,062,626	3,203,048
Interest Rate Options Written [Member]
Derivative [Line Items]
Total		106,238	106,009
Interest Rate Options Purchased [Member]
Derivative [Line Items]
Total		110,682	107,561
Foreign exchange contracts [Member]
Derivative [Line Items]
Total		1,321,842	1,144,808
Foreign Exchange Swaps, Futures and Forwards [Member]
Derivative [Line Items]
Total		1,169,693	1,052,088
Foreign Exchange Options Written [Member]
Derivative [Line Items]
Total		54,583	30,567
Foreign Exchange Options Purchased [Member]
Derivative [Line Items]
Total		55,027	31,069
Foreign Exchange Spot [Member]
Derivative [Line Items]
Total		42,539	31,084
Commodities, equities and precious metals contracts [Member]
Derivative [Line Items]
Total		137,864	110,159
Commodities, Equities and Precious Metals, Swaps, Futures and Forwards [Member]
Derivative [Line Items]
Total		56,428	41,328
Commodities, Equities and Precious Metals Options Written [Member]
Derivative [Line Items]
Total		35,191	28,595
Commodities, Equities and Precious Metals Options Purchased [Member]
Derivative [Line Items]
Total		46,245	40,236
Credit contracts [Member]
Derivative [Line Items]
Total		122,874	97,298
Other Contracts [Member]
Derivative [Line Items]
Total	[1]	$ 969	$ 736
[1]	Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares.

Fair Value Option - Additional

Fair Value Option - Additional Information (Details) - Loans Receivable [Member] - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value option loan in nonaccrual status	$ 0	$ 0
Fair value option, loans 90 days or more past due	$ 0	$ 0

Fair Value Option - Summary of

Fair Value Option - Summary of Fair Value and Unpaid Principal Balance (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Loans Receivable [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Commercial loans held for sale, Fair Value	$ 128	$ 109
Commercial loans held for sale, Unpaid Principal Balance	136	120
Fair value over (under) unpaid principal balance	(8)	(11)
Securities sold under repurchase agreements [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value over (under) unpaid principal balance	0	0
Securities sold under repurchase agreements, Fair Value	222	560
Securities sold under repurchase agreements, Unpaid Principal Balance	222	560
Long-term debt [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value over (under) unpaid principal balance	410	185
Fixed rate long-term debt, Fair Value	2,160	1,935
Fixed rate long-term debt, Unpaid Principal Balance	1,750	1,750
Long-term debt [Member] | Structured Notes [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value over (under) unpaid principal balance	821	(232)
Hybrid instruments, Unpaid Principal Balance	8,998	9,546
Hybrid instruments, structured notes, Fair Value	9,819	9,314
Structured Deposits [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value over (under) unpaid principal balance	(17)	(287)
Hybrid instruments, structured deposits, Fair Value	8,455	8,154
Hybrid instruments, Unpaid Principal Balance	$ 8,472	$ 8,441

Fair Value Option - Components

Fair Value Option - Components of Gain (Loss) on Instruments at Fair Value and Related Derivatives (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items]
Mark-to-market on related derivatives	$ 497	$ 105	$ 1,549		$ (402)
Gain (loss) on instruments designated at fair value and related derivatives	(17)	4	(26)		34
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member]
Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items]
Interest rate and other components	(522)	(100)	(1,603)	[1]	429	[1]
Credit risk component, total	0	(1)	3	[2]	3	[2]
Total mark-to-market on financial instruments designated at fair value	(522)	(101)	(1,600)		432
Mark-to-market on related derivatives	496	94	1,555		(422)
Net realized gain on related long-term debt derivatives	9	11	19		24
Gain (loss) on instruments designated at fair value and related derivatives	(17)	4	(26)		34
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Loans [Member]
Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items]
Interest rate and other components	0	0	0	[1]	0	[1]
Credit risk component, assets	0	(1)	3	[2]	3	[2]
Total mark-to-market on financial instruments designated at fair value	0	(1)	3		3
Mark-to-market on related derivatives	0	0	0		0
Net realized gain on related long-term debt derivatives	0	0	0		0
Gain (loss) on instruments designated at fair value and related derivatives	0	(1)	3		3
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Securities sold under repurchase agreements [Member]
Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items]
Interest rate and other components	0	1	0	[1]	0	[1]
Credit risk component, liabilities	0	0	0	[2]	0	[2]
Total mark-to-market on financial instruments designated at fair value	0	1	0		0
Mark-to-market on related derivatives	0	0	0		0
Net realized gain on related long-term debt derivatives	0	0	0		0
Gain (loss) on instruments designated at fair value and related derivatives	0	1	0		0
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Long-term debt [Member]
Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items]
Interest rate and other components	(100)	34	(169)	[1]	122	[1]
Credit risk component, liabilities	0	0	0	[2]	0	[2]
Total mark-to-market on financial instruments designated at fair value	(100)	34	(169)		122
Mark-to-market on related derivatives	83	(33)	136		(110)
Net realized gain on related long-term debt derivatives	9	11	19		24
Gain (loss) on instruments designated at fair value and related derivatives	(8)	12	(14)		36
Gain (Loss) on Instruments Designated at Fair Value and Related Derivatives [Member] | Hybrid Instrument [Member]
Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items]
Interest rate and other components	(422)	(135)	(1,434)	[1]	307	[1]
Credit risk component, liabilities	0	0	0	[2]	0	[2]
Total mark-to-market on financial instruments designated at fair value	(422)	(135)	(1,434)		307
Mark-to-market on related derivatives	413	127	1,419		(312)
Net realized gain on related long-term debt derivatives	0	0	0		0
Gain (loss) on instruments designated at fair value and related derivatives	$ (9)	$ (8)	$ (15)		$ (5)
[1]	As it relates to hybrid instruments, interest rate and other components primarily includes interest rate, foreign exchange and equity contract risks.
[2]	he fair value movement on fair value option liabilities attributable to our own credit spread is recorded in other comprehensive income (loss).

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss - (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Unrealized gains (losses) on investment securities:
Balance at beginning of period		$ (340)	$ (494)	$ (519)	$ (299)
Other comprehensive income for period:
Net unrealized gains (losses) arising during period, net of tax		235	(73)	415	(266)
Reclassification adjustment for (gains) losses realized in net income, net of tax	[1]	(18)	(7)	(23)	(11)
Amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity realized in net income, net of tax	[2]	3	4	7	6
Total other comprehensive income (loss) for period		220	(76)	399	(271)
Balance at end of period		(120)	(570)	(120)	(570)
Unrealized gains (losses) on fair value option liabilities attributable to our own credit spread:
Balance at beginning of period		190	(11)	301	(23)
Other comprehensive income (loss) for period:
Net unrealized gains (losses) arising during period, net of tax		7	129	(104)	141
Total other comprehensive income (loss) for period		7	129	(104)	141
Balance at end of period		197	118	197	118
Unrealized gains (losses) on derivatives designated as cash flow hedges:
Balance at beginning of period		(145)		(159)
Balance at beginning of period			(197)		(199)
Other comprehensive income (loss) for period:
Net unrealized gains (losses) arising during period, net of tax		(1)		5
Reclassification adjustment for losses realized in net income, net of tax	[3]	6		14
Total other comprehensive income for period		5		19
Net unrealized gains (losses) arising during period, net of tax			6		5
Reclassification adjustment for (gains) losses realized in net income, net of tax	[3]		4		7
Total other comprehensive income (loss) for period			10		12
Balance at end of period			(187)		(187)
Balance at end of period		(140)		(140)
Pension and postretirement benefit liability:
Balance at beginning of period		8	4	11	3
Change in unfunded pension and postretirement liability, net of tax		0	(1)	(3)	0
Total other comprehensive loss for period		0	(1)	(3)	0
Balance at end of period		8	3	8	3
Total accumulated other comprehensive loss at end of period		$ (55)	$ (636)	$ (55)	(636)	$ (366)
Accounting Standards Update 2016-01, Equity Investments Previously Classified as Available-for-sale [Member] | Unrealized Gains (Losses) on Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cumulative effect of new accounting principle in period of adoption						0	$ 4
Accounting Standards Update 2018-02 [Member] | Unrealized Gains (Losses) on Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cumulative effect of new accounting principle in period of adoption						0	(53)
Accounting Standards Update 2018-02 [Member] | Unrealized Gains (Losses) on Fair Value Option Liabilities Attributable to Our Own Credit Spread [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cumulative effect of new accounting principle in period of adoption						0	(4)
Accounting Standards Update 2018-02 [Member] | Unrealized Gains (Losses) on Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cumulative effect of new accounting principle in period of adoption						0	(35)
Accounting Standards Update 2018-02 [Member] | Pension and Postretirement Benefit Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cumulative effect of new accounting principle in period of adoption						$ 0	$ 1
As Previously Reported [Member]
Unrealized gains (losses) on investment securities:
Balance at beginning of period					(250)
Unrealized gains (losses) on fair value option liabilities attributable to our own credit spread:
Balance at beginning of period					(19)
Unrealized gains (losses) on derivatives designated as cash flow hedges:
Balance at beginning of period					(164)
Pension and postretirement benefit liability:
Balance at beginning of period					$ 2
[1]	Amount reclassified to net income is included in other securities gains, net in our consolidated statement of income.
[2]	Amount amortized to net income is included in interest income in our consolidated statement of income. During 2014, we transferred securities from available-for-sale to held-to-maturity. At the date of transfer, AOCI included net pretax unrealized losses related to the transferred securities which are being amortized over the remaining contractual life of each security as an adjustment of yield in a manner consistent with the amortization of any premium or discount.
[3]	Amount reclassified to net income is included in net interest income in our consolidated statement of income.

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Tax (benefit) expense included in net unrealized gains (losses), investment securities	$ 73	$ (22)	$ 128	$ (85)
Tax included in reclassification, investment securities	(5)	(3)	(7)	(4)
Tax included in amortization, investment securities	1	1	2	2
Tax (benefit) expense included in net unrealized gains (losses), fair value option liabilities	2	41	(33)	46
Tax (benefit) expense included in net unrealized gains (losses), cash flow hedges			1
Tax (benefit) expense included in net unrealized gains (losses), cash flow hedges (less than $1 million)	(1)	2		2
Tax included in reclassification, cash flow hedges			5
Tax included in reclassification, cash flow hedges	3	1		2
Tax included in net unrealized gains (losses), pension and postretirement benefit liability	$ 0	$ 1	$ (1)	$ 1
Unrealized Gains (Losses) on Investment Securities [Member] | Accounting Standards Update 2016-01, Equity Investments Previously Classified as Available-for-sale [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Cumulative effect of new accounting principle in period of adoption, tax					$ 0	$ 2

Pension and Other Postretirem_3

Pension and Other Postretirement Benefits-Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Postretirement Plans Other Than Pensions [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1	$ 1	$ 1	$ 1
Amortization of net actuarial (gain) loss	(1)	0	(1)	0
Net periodic benefit cost	0	1	0	1
HSBC North America [Member] | HSBC North America Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	14	15	29	30
Expected return on plan assets	(19)	(19)	(37)	(40)
Amortization of net actuarial (gain) loss	5	5	12	10
Administrative costs	1	1	2	2
Net periodic benefit cost	$ 1	$ 2	$ 6	$ 2

Fee Income from Contracts wit_3

Fee Income from Contracts with Customers (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018		Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		$ 303	$ 323	$ 575		$ 634
Other non-fee revenues		133	214	251		416
Total other revenues	[1]	436	537	826	[2]	1,050	[2]
Deferred fee income		2		2				$ 2
Credit card fees, net [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		18	15	30		26
Interchange fees		26	22	48		43
Rewards program costs		10	9	22		21
Trust and investment management fees [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		31	34	61		72
Account services [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		68	79	133	[3]	148	[3]
Credit facilities [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		81	86	150		164
Other fees [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		13	19	26	[3]	32	[3]
Other fees and commissions [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		162	184	309		344
Servicing and other fees from HSBC affiliates [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers		88	87	169		186
Insurance [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers	[4]	$ 4	3	$ 6		6
Reclassified Amount [Member] | Account services [Member]
Disaggregation of Revenue [Line Items]
Fee income from contracts with customers			$ 6			$ 10
[1]	See Note 15, "Business Segments," for a reconciliation of total other revenues on a U.S. GAAP basis to other operating income for each business segment under the Group Reporting Basis.
[2]	Represents adjustments associated with differences between U.S. GAAP and the Group Reporting Basis.
[3]	During the fourth quarter of 2018, we concluded that certain wire transfer fees would be better presented in account services as opposed to other fees. As a result, we have reclassified $6 million and $10 million of wire transfer fees from other fees to account services during the three and six months ended June 30, 2018 to conform with the current year presentation.
[4]	Included within other income (loss) in the consolidated statement of income.

Related Party Transactions - Su

Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Millions		Jun. 30, 2019		Dec. 31, 2018		Jun. 30, 2018
Assets:
Cash and due from banks		$ 1,196		$ 1,514
Interest bearing deposits with banks		11,736		15,700
Trading assets		33,502		21,978
Loans		72,478		68,978		$ 66,399
Other		7,342		6,325
Total assets		184,063	[1]	172,448	[1]	180,687
Liabilities:
Deposits		116,961		110,955		114,355
Trading liabilities		4,026		3,643
Short-term borrowings		8,649		4,180
Long-term debt		30,849		30,628
Other		4,944		2,536
Total liabilities	[1]	165,429		151,942
Affiliated Entity [Member]
Assets:
Cash and due from banks		250		245
Interest bearing deposits with banks		790		1,000
Trading assets		298		102
Loans		3,096		2,274		$ 1,895
Other		289		169
Total assets		4,723		3,790
Liabilities:
Deposits		13,301		12,000
Trading liabilities		157		349
Short-term borrowings		1,518		638
Long-term debt		7,847		7,845
Other	[2]	392		333
Total liabilities		$ 23,215		$ 21,165
[1]	The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at June 30, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 17, "Variable Interest Entities," for additional information. Assets: Other assets $98 million and $112 million. Total assets $98 million and $112 million respectively. Liabilities: Long-term debt $66 million and $66 million, Interest, taxes and other liabilities $32 million and $37 million. Total liabilities $98 million and $103 million, respectively.
[2]	Other assets and other liabilities primarily consist of derivative balances associated with hedging activities and other miscellaneous account receivables and payables.

Related Party Transactions - _2

Related Party Transactions - Summary of Related Party Transactions (Income - Expense) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Related Party Transaction [Line Items]
Interest income		$ 1,301	$ 1,147	$ 2,578	$ 2,221
Interest expense		(761)	(592)	(1,476)	(1,114)
Net interest income		540	555	1,102	1,107
Trading revenue (expense)		123	192	256	355
Servicing and other fees from HSBC affiliates: [Abstract]
Other revenues		303	323	575	634
Gain (loss) on instruments designated at fair value and related derivatives		(17)	4	(26)	34
Support services from HSBC affiliates:
Total support services from HSBC affiliates		(411)	(405)	(791)	(816)
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Interest income		47	24	90	46
Interest expense		(152)	(90)	(276)	(168)
Net interest income		(105)	(66)	(186)	(122)
Trading revenue (expense)		(9)	(627)	(1,523)	531
Servicing and other fees from HSBC affiliates: [Abstract]
Gain (loss) on instruments designated at fair value and related derivatives		412	135	1,420	(303)
Support services from HSBC affiliates:
Total support services from HSBC affiliates		(411)	(405)	(791)	(816)
Rental income from HSBC affiliates, net	[1]	12	14	24	26
Stock based compensation expense with HSBC	[2]	(8)	(10)	(14)	(15)
HSBC Markets (USA) Inc. (HMUS) and subsidiaries [Member]
Support services from HSBC affiliates:
Total support services from HSBC affiliates		(23)	(25)	(50)	(56)
Other HSBC affiliates [Member]
Support services from HSBC affiliates:
Total support services from HSBC affiliates		(90)	(70)	(166)	(152)
HSBC Technology and Services (USA) (HTSU) [Member]
Support services from HSBC affiliates:
Total support services from HSBC affiliates		(298)	(310)	(575)	(608)
Servicing and other fees from HSBC affiliates [Member]
Servicing and other fees from HSBC affiliates: [Abstract]
Other revenues		88	87	169	186
Servicing and other fees from HSBC affiliates [Member] | Affiliated Entity [Member]
Servicing and other fees from HSBC affiliates: [Abstract]
Other revenues		88	87	169	186
Servicing and other fees from HSBC affiliates [Member] | HSBC Bank Plc [Member]
Servicing and other fees from HSBC affiliates: [Abstract]
Other revenues		46	43	81	84
Servicing and other fees from HSBC affiliates [Member] | HSBC Markets (USA) Inc. (HMUS) and subsidiaries [Member]
Servicing and other fees from HSBC affiliates: [Abstract]
Other revenues		27	30	57	61
Servicing and other fees from HSBC affiliates [Member] | Other HSBC affiliates [Member]
Servicing and other fees from HSBC affiliates: [Abstract]
Other revenues		$ 15	$ 14	$ 31	$ 41
[1]	We receive rental income from our affiliates, and in some cases pay rental expense to our affiliates, for rent on certain office space. Net rental income from our affiliates is recorded as a component of occupancy expense, net in our consolidated statement of income.
[2]	Employees may participate in one or more stock compensation plans sponsored by HSBC. These expenses are included in salaries and employee benefits in our consolidated statement of income. Certain employees are also eligible to participate in a defined benefit pension plan and other postretirement plans sponsored by HSBC North America which are discussed in Note 12, "Pension and Other Postretirement Benefits."

Related Party Transactions - _3

Related Party Transactions - Summary of Loans (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
HMUS [Member]
Related Party Transaction [Line Items]
Loans and leases receivable from related parties	$ 2,835	$ 2,235
HSBC Bank Canada [Member]
Related Party Transaction [Line Items]
Loans and leases receivable from related parties	250	0
Other short-term affiliate lending [Member]
Related Party Transaction [Line Items]
Loans and leases receivable from related parties	11	39
HSBC Affiliates [Member]
Related Party Transaction [Line Items]
Loans and leases receivable from related parties	$ 3,096	$ 2,274

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Long-term debt		$ 30,849,000,000		$ 30,628,000,000
Derivative, notional amount		5,516,710,000,000		5,556,668,000,000
Preferred stock issued		1,265,000,000		1,265,000,000
Return of capital to parent		2,400,000,000	$ 0
HNAH [Member]
Related Party Transaction [Line Items]
Long-term debt		7,800,000,000		7,800,000,000
Maximum borrowing capacity		150,000,000		150,000,000
Amount outstanding under the loan agreement		0		0
Preferred stock issued		1,265,000,000		1,265,000,000
Preferred stock outstanding		1,265,000,000		1,265,000,000
Return of capital to parent	$ 2,400,000,000
HMUS [Member]
Related Party Transaction [Line Items]
Extended loans and lines of credit		12,800,000,000		12,800,000,000
Loans and leases receivable from related parties		2,835,000,000		2,235,000,000
Amount outstanding on line of credit		2,800,000,000		2,200,000,000
HSBC Bank Canada [Member]
Related Party Transaction [Line Items]
Extended loans and lines of credit		500,000,000		500,000,000
Loans and leases receivable from related parties		250,000,000		0
Amount outstanding on line of credit		250,000,000		0
Other HSBC affiliates [Member]
Related Party Transaction [Line Items]
Extended loans and lines of credit		4,200,000,000
Loans and leases receivable from related parties		11,000,000		39,000,000
Amount outstanding on line of credit		0		0
HSBC Affiliates [Member]
Related Party Transaction [Line Items]
Long-term debt		7,847,000,000		7,845,000,000
Loans and leases receivable from related parties		3,096,000,000		2,274,000,000
Derivative, notional amount		935,300,000,000		809,500,000,000
Fair value of derivative assets and liabilities		337,000,000		$ 108,000,000
Fixed Rate Note Maturing March 2021 [Member] | HNAH [Member] | Senior debt [Member]
Related Party Transaction [Line Items]
Long-term debt		1,500,000,000
Fixed Rate Note Maturing May 2021 [Member] | HNAH [Member] | Senior debt [Member]
Related Party Transaction [Line Items]
Long-term debt		2,000,000,000
Floating Rate Note Maturing May 2025 [Member] | HNAH [Member] | Subordinated Debt [Member]
Related Party Transaction [Line Items]
Long-term debt		800,000,000
Fixed Rate Note Maturing September 2025 [Member] | HNAH [Member] | Senior debt [Member]
Related Party Transaction [Line Items]
Long-term debt		2,000,000,000
Fixed Rate Note Maturing March 2026 [Member] | HNAH [Member] | Senior debt [Member]
Related Party Transaction [Line Items]
Long-term debt		$ 1,500,000,000

Business Segments Additional In

Business Segments Additional Information (Details)	6 Months Ended
	Jun. 30, 2019segment
Segment Reporting [Abstract]
Number of reportable segments	5

Business Segments - Summary on

Business Segments - Summary on Reconciliation of Results Under Ifrs to Us Gaap (Detail) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2019		Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018		Dec. 31, 2018
Operating Statistics [Line Items]
Net Interest Income		$ 610		$ 632	$ 1,234		$ 1,245
Group Reporting Basis Other operating income		365		469	703	[1]	917	[1]
Group Reporting Basis Total operating income		975		1,101	1,937		2,162
Expected credit losses/provision for credit losses		25		(175)	35		(196)
Group Reporting Basis Revenues		950		1,276	1,902		2,358
Operating Expenses	[1]	761		804	1,509		2,089	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		189		472	393		269
Total Assets		215,763		214,855	215,763		214,855
Group Reporting Basis Total loans, net		70,328		65,261	70,328		65,261
Group Reporting Basis Goodwill		1,260		1,260	1,260		1,260
Group Reporting Basis Total deposits		100,081		101,729	100,081		101,729
Net interest income		540		555	1,102		1,107
Other operating income	[3]	436		537	826	[1]	1,050	[1]
Total operating income		976		1,092	1,928		2,157
Provision for credit losses		46		(45)	104		(116)
Total income		930		1,137	1,824		2,273
Operating expenses	[1]	774		786	1,524		2,068	[2]
Income before income tax		156		351	300		205
Total assets		184,063	[4]	180,687	184,063	[4]	180,687		$ 172,448	[4]
Total loans, net		71,865		65,868	71,865		65,868		68,437
Goodwill		1,607		1,607	1,607		1,607		1,607
Total deposits		116,961		114,355	116,961		114,355		$ 110,955
Group Reporting Basis Adjustments [Member]
Operating Statistics [Line Items]
Net Interest Income		3		6	9		14
Group Reporting Basis Other operating income		(3)		(9)	(20)	[1]	(20)	[1]
Group Reporting Basis Total operating income		0		(3)	(11)		(6)
Expected credit losses/provision for credit losses		23		118	64		67
Group Reporting Basis Revenues		(23)		(121)	(75)		(73)
Operating Expenses	[1]	10		0	18		(9)	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		(33)		(121)	(93)		(64)
Total Assets		(31,700)		(34,168)	(31,700)		(34,168)
Group Reporting Basis Total loans, net		(2,340)		(1,341)	(2,340)		(1,341)
Group Reporting Basis Goodwill		347		347	347		347
Group Reporting Basis Total deposits		(3,434)		(3,168)	(3,434)		(3,168)
Group Reporting Basis Reclassifications [Member]
Operating Statistics [Line Items]
Net Interest Income		(73)		(83)	(141)		(152)
Group Reporting Basis Other operating income		74		77	143	[1]	153	[1]
Group Reporting Basis Total operating income		1		(6)	2		1
Expected credit losses/provision for credit losses		(2)		12	5		13
Group Reporting Basis Revenues		3		(18)	(3)		(12)
Operating Expenses	[1]	3		(18)	(3)		(12)	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		0		0	0		0
Total Assets		0		0	0		0
Group Reporting Basis Total loans, net		3,877		1,948	3,877		1,948
Group Reporting Basis Goodwill		0		0	0		0
Group Reporting Basis Total deposits		20,314		15,794	20,314		15,794
RBWM [Member] | Operating Segments [Member]
Operating Statistics [Line Items]
Net Interest Income		217		225	438		441
Group Reporting Basis Other operating income		74		71	139	[1]	164	[1]
Group Reporting Basis Total operating income		291		296	577		605
Expected credit losses/provision for credit losses		12		3	33		6
Group Reporting Basis Revenues		279		293	544		599
Operating Expenses	[1]	305		341	616		666	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		(26)		(48)	(72)		(67)
Total Assets		18,907		18,691	18,907		18,691
Group Reporting Basis Total loans, net		17,031		16,695	17,031		16,695
Group Reporting Basis Goodwill		581		581	581		581
Group Reporting Basis Total deposits		33,606		32,672	33,606		32,672
CMB [Member] | Operating Segments [Member]
Operating Statistics [Line Items]
Net Interest Income		202		195	403		381
Group Reporting Basis Other operating income		55		58	113	[1]	113	[1]
Group Reporting Basis Total operating income		257		253	516		494
Expected credit losses/provision for credit losses		9		(36)	15		(46)
Group Reporting Basis Revenues		248		289	501		540
Operating Expenses	[1]	142		139	280		290	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		106		150	221		250
Total Assets		26,735		23,851	26,735		23,851
Group Reporting Basis Total loans, net		25,513		22,879	25,513		22,879
Group Reporting Basis Goodwill		358		358	358		358
Group Reporting Basis Total deposits		23,554		23,643	23,554		23,643
GBM [Member] | Operating Segments [Member]
Operating Statistics [Line Items]
Net Interest Income		136		151	287		300
Group Reporting Basis Other operating income		170		252	345	[1]	449	[1]
Group Reporting Basis Total operating income		306		403	632		749
Expected credit losses/provision for credit losses		2		(143)	(15)		(157)
Group Reporting Basis Revenues		304		546	647		906
Operating Expenses	[1]	210		209	416		425	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		94		337	231		481
Total Assets		87,114		79,535	87,114		79,535
Group Reporting Basis Total loans, net		19,599		17,786	19,599		17,786
Group Reporting Basis Goodwill		0		0	0		0
Group Reporting Basis Total deposits		29,674		32,749	29,674		32,749
PB [Member] | Operating Segments [Member]
Operating Statistics [Line Items]
Net Interest Income		37		43	74		90
Group Reporting Basis Other operating income		17		16	33	[1]	36	[1]
Group Reporting Basis Total operating income		54		59	107		126
Expected credit losses/provision for credit losses		2		0	1		(3)
Group Reporting Basis Revenues		52		59	106		129
Operating Expenses	[1]	56		61	109		122	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		(4)		(2)	(3)		7
Total Assets		6,952		7,075	6,952		7,075
Group Reporting Basis Total loans, net		5,863		6,036	5,863		6,036
Group Reporting Basis Goodwill		321		321	321		321
Group Reporting Basis Total deposits		7,226		8,112	7,226		8,112
CC [Member] | Operating Segments [Member]
Operating Statistics [Line Items]
Net Interest Income		18		18	32		33
Group Reporting Basis Other operating income		49		72	73	[1]	155	[1]
Group Reporting Basis Total operating income		67		90	105		188
Expected credit losses/provision for credit losses		0		1	1		4
Group Reporting Basis Revenues		67		89	104		184
Operating Expenses	[1]	48		54	88		586	[2]
Group Reporting Basis Profit (Loss) Before Income Tax Expense		19		35	16		(402)
Total Assets		76,055		85,703	76,055		85,703
Group Reporting Basis Total loans, net		2,322		1,865	2,322		1,865
Group Reporting Basis Goodwill		0		0	0		0
Group Reporting Basis Total deposits		$ 6,021		$ 4,553	$ 6,021		$ 4,553
[1]	Represents adjustments associated with differences between U.S. GAAP and the Group Reporting Basis.
[2]	Represents differences in financial statement presentation between U.S. GAAP and the Group Reporting Basis.
[3]	See Note 15, "Business Segments," for a reconciliation of total other revenues on a U.S. GAAP basis to other operating income for each business segment under the Group Reporting Basis.
[4]	The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at June 30, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 17, "Variable Interest Entities," for additional information. Assets: Other assets $98 million and $112 million. Total assets $98 million and $112 million respectively. Liabilities: Long-term debt $66 million and $66 million, Interest, taxes and other liabilities $32 million and $37 million. Total liabilities $98 million and $103 million, respectively.

Retained Earnings and Regulat_3

Retained Earnings and Regulatory Capital Requirements - Capital Amounts and Ratios in Accordance With Current Banking Regulations (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
HSBC USA Inc [Member]
Common equity Tier 1 ratio:
Capital Amount, Common Equity Tier 1		$ 15,678	$ 17,459
Well Capitalized Ratio, Common Equity Tier 1	[1],[2]	4.50%	4.50%
Actual Ratio, Common equity Tier 1		12.40%	13.60%
Tier 1 capital ratio:
Capital Amount, Tier 1 capital		$ 16,943	$ 18,724
Well-Capitalized Ratio, Tier 1 capital	[1]	6.00%	6.00%
Actual Ratio, Tier 1 Capital		13.40%	14.60%
Total capital ratio:
Capital Amount		$ 20,342	$ 21,972
Well-Capitalized Ratio	[1]	10.00%	10.00%
Actual Ratio, Total Capital		16.10%	17.20%
Tier 1 leverage ratio:
Capital Amount, Tier 1 leverage capital		$ 16,943	$ 18,724
Well-Capitalized Ratio, Tier 1 leverage capital	[1],[2]	4.00%	4.00%
Actual Ratio, Tier 1 leverage capital		9.60%	11.00%
Supplementary Leverage Ratio [Abstract]
Capital Amount, Supplementary Leverage Ratio		$ 16,943	$ 18,724
Well-capitalized Ratio, Supplementary Leverage Ratio	[1],[3]	3.00%	3.00%
Actual Ratio, Supplementary Leverage Ratio		6.80%	7.60%
Risk weighted assets:
Risk Weighted Assets	[4]	$ 126,416	$ 127,917
Adjusted Quarterly Average Assets [Abstract]
Adjusted quarterly average assets	[5]	176,467	170,565
Total Leverage Exposure [Abstract]
Total leverage exposure	[6]	248,581	245,796
HSBC Bank USA [Member]
Common equity Tier 1 ratio:
Capital Amount, Common Equity Tier 1		$ 17,752	$ 19,456
Well Capitalized Ratio, Common Equity Tier 1	[1]	6.50%	6.50%
Actual Ratio, Common equity Tier 1		14.40%	15.70%
Tier 1 capital ratio:
Capital Amount, Tier 1 capital		$ 20,252	$ 21,956
Well-Capitalized Ratio, Tier 1 capital	[1]	8.00%	8.00%
Actual Ratio, Tier 1 Capital		16.50%	17.70%
Total capital ratio:
Capital Amount		$ 23,655	$ 25,293
Well-Capitalized Ratio	[1]	10.00%	10.00%
Actual Ratio, Total Capital		19.20%	20.40%
Tier 1 leverage ratio:
Capital Amount, Tier 1 leverage capital		$ 20,252	$ 21,956
Well-Capitalized Ratio, Tier 1 leverage capital	[1]	5.00%	5.00%
Actual Ratio, Tier 1 leverage capital		11.70%	13.10%
Supplementary Leverage Ratio [Abstract]
Capital Amount, Supplementary Leverage Ratio		$ 20,252	$ 21,956
Well-capitalized Ratio, Supplementary Leverage Ratio	[1],[3]	3.00%	3.00%
Actual Ratio, Supplementary Leverage Ratio		8.30%	9.10%
Risk weighted assets:
Risk Weighted Assets	[4]	$ 123,021	$ 124,112
Adjusted Quarterly Average Assets [Abstract]
Adjusted quarterly average assets	[5]	173,320	168,154
Total Leverage Exposure [Abstract]
Total leverage exposure	[6]	$ 243,943	$ 242,264
[1]	HSBC USA and HSBC Bank USA are categorized as "well-capitalized," as defined by their principal regulators. To be categorized as well-capitalized under regulatory guidelines, a banking institution must have the ratios reflected in the above table, and must not be subject to a directive, order, or written agreement to meet and maintain specific capital levels.
[2]	There are no common equity Tier 1 or Tier 1 leverage ratio components in the definition of a well-capitalized bank holding company. The ratios shown are the regulatory minimum ratios.
[3]	There is no SLR component in the definition of a well-capitalized banking institution.
[4]	Calculated using the generally-applicable Standardized Approach.
[5]	Represents the Tier 1 leverage ratio denominator which reflects quarterly average assets adjusted for amounts permitted to be deducted from Tier 1 capital.
[6]	Represents the SLR denominator which includes adjusted quarterly average assets plus certain off-balance sheet exposures.

Retained Earnings and Regulat_4

Retained Earnings and Regulatory Capital Requirements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Return of capital to parent		$ 2,400	$ 0
Restricted cash		$ 2,343		$ 2,205
HSBC Bank USA [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Return of capital to parent	$ 2,400
HNAH [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Return of capital to parent	$ 2,400

Variable Interest Entities - Su

Variable Interest Entities - Summary of Assets and Liabilities Related to Consolidated Variable Interest Entities (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Variable interest entities [Member]
Variable Interest Entity [Line Items]
Consolidated Assets	$ 98	$ 112
Consolidated Liabilities	98	103
Other assets [Member] | Low income housing limited liability partnership [Member]
Variable Interest Entity [Line Items]
Consolidated Assets	98	112
Long-term debt [Member] | Low income housing limited liability partnership [Member]
Variable Interest Entity [Line Items]
Consolidated Liabilities	66	66
Interest, taxes and other liabilities [Member] | Low income housing limited liability partnership [Member]
Variable Interest Entity [Line Items]
Consolidated Liabilities	$ 32	$ 37

Variable Interest Entities - Va

Variable Interest Entities - Variable Interests Held by Us and Our Maximum Exposure to Loss Rising From Our Involvements in Those VIEs (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Total Assets Held by Unconsolidated VIEs	$ 3,563	$ 4,611
Variable Interest Held Classified as Assets	1,052	2,257
Variable Interests Held Classified as Liabilities	271	229
Maximum Exposure to Loss	2,085	3,457
Structured note vehicles [Member]
Variable Interest Entity [Line Items]
Total Assets Held by Unconsolidated VIEs	1,526	3,033
Variable Interest Held Classified as Assets	510	1,803
Variable Interests Held Classified as Liabilities	11	20
Maximum Exposure to Loss	1,515	3,003
Limited partnership investments [Member]
Variable Interest Entity [Line Items]
Total Assets Held by Unconsolidated VIEs	2,037	1,578
Variable Interest Held Classified as Assets	542	454
Variable Interests Held Classified as Liabilities	260	209
Maximum Exposure to Loss	$ 570	$ 454

Variable Interest Entities - Ad

Variable Interest Entities - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maximum exposure to loss		$ 2,085	$ 3,457
Carrying value of structured note vehicle		3,563	4,611
Structured note vehicles [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maximum exposure to loss		1,515	3,003
Loss on structured note settlement	$ 39
Carrying value of structured note vehicle		$ 1,526	$ 3,033
Trading Assets [Member] | Structured note vehicles [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Carrying value of structured note vehicle	$ 1,293

Guarantee Arrangements, Pledg_3

Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Carrying Value and Contractual Amounts of our Sell Protection Credit Derivatives and Major Off-Balance Sheet Guarantee Arrangements (Detail) - USD ($) $ in Millions		Jun. 30, 2019		Dec. 31, 2018
Guarantor Obligations [Line Items]
Carrying Value		$ (268)		$ (562)
Notional/maximum exposure to loss		63,121	[1]	54,356
Credit derivatives [Member]
Guarantor Obligations [Line Items]
Carrying Value	[2],[3]	(268)		(562)
Notional/maximum exposure to loss	[2],[3]	54,256		45,384
Financial standby letters of credit, net of participations [Member]
Guarantor Obligations [Line Items]
Carrying Value	[4],[5]	0		0
Notional/maximum exposure to loss	[4],[5]	5,376		5,302
Performance standby letters of credit, net of participations [Member]
Guarantor Obligations [Line Items]
Carrying Value	[4],[5]	0		0
Notional/maximum exposure to loss	[4],[5]	3,489		3,670
Affiliated Entity [Member] | Credit derivatives [Member]
Guarantor Obligations [Line Items]
Notional/maximum exposure to loss		32,481		25,734
Affiliated Entity [Member] | Financial and performance standby letters of credit [Member]
Guarantor Obligations [Line Items]
Notional/maximum exposure to loss		$ 1,419		$ 1,321
[1]	External ratings for most of the obligors are not available. Presented above are the internal credit ratings which are developed using similar methodologies and rating scale equivalent to external credit ratings for purposes of classification as investment grade and non-investment grade.
[2]	For credit derivatives, the maximum loss is represented by the notional amounts without consideration of mitigating effects from collateral or recourse arrangements.
[3]	Includes $32,481 million and $25,734 million of notional issued for the benefit of HSBC affiliates at June 30, 2019 and December 31, 2018, respectively.
[4]	For standby letters of credit, maximum loss represents losses to be recognized assuming the letters of credit have been fully drawn and the obligors have defaulted with zero recovery.
[5]	Includes $1,419 million and $1,321 million of both financial and performance standby letters of credit issued for the benefit of HSBC affiliates at June 30, 2019 and December 31, 2018, respectively.

Guarantee Arrangements, Pledg_4

Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Net Credit Derivative Positions (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Credit Derivatives [Line Items]
Net position, Carrying/Fair Value	[1]	$ (124)	$ 39
Notional	[1]	14,362	6,530
Sell-protection credit derivative positions [Member]
Credit Derivatives [Line Items]
Carrying/Fair Value		(268)	(562)
Notional		54,256	45,384
Buy-protection credit derivative positions [Member]
Credit Derivatives [Line Items]
Carrying/Fair Value		144	601
Notional		$ 68,618	$ 51,914
[1]	Positions are presented net in the table above to provide a complete analysis of our risk exposure and depict the way we manage our credit derivative portfolio. The offset of the sell-protection credit derivatives against the buy-protection credit derivatives may not be legally binding in the absence of master netting agreements with the same counterparty. Furthermore, the credit loss triggering events for individual sell protection credit derivatives may not be the same or occur in the same period as those of the buy protection credit derivatives thereby not providing an exact offset.

Guarantee Arrangements, Pledg_5

Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended	36 Months Ended
		Jun. 30, 2018	Dec. 31, 2007	Jun. 30, 2019	Dec. 31, 2018
Guarantor Obligations [Line Items]
Deferred fees				$ 2	$ 2
Carrying value of swap				5,516,710	5,556,668
Pledged assets not separately reported, trading assets	[1]			7,429	2,465
Collateral accepted under security resale agreements, fair value				12,205	13,004
Collateral accepted under security repurchase agreements but not reported on the balance sheet that can be sold or repledged, fair value				11,255	11,904
Collateral accepted under security repurchase agreements that has been sold or repledged under repurchase agreements or to cover short sales				436	243
HSBC Securities [Member]
Guarantor Obligations [Line Items]
Whole loan securitization			$ 24,000
Securities available-for-sale [Member]
Guarantor Obligations [Line Items]
Securities pledged as collateral that can be sold or repledged by the secured party, fair value				2,290	822
Trading assets [Member]
Guarantor Obligations [Line Items]
Pledged assets not separately reported, trading assets				7,402	2,464
Obligation to Repurchase Receivables Sold [Member]
Guarantor Obligations [Line Items]
Outstanding repurchase demands				4	2
Other liabilities [Member]
Guarantor Obligations [Line Items]
Allowance for credit losses on unfunded standby letters of credit				17	16
Other liabilities [Member] | Standby Letters of Credit [Member]
Guarantor Obligations [Line Items]
Deferred fees				47	43
Swap [Member]
Guarantor Obligations [Line Items]
Carrying value of swap				40	40
Mortgage Securitization Activity Related Litigation [Member] | HSBC Securities [Member]
Guarantor Obligations [Line Items]
Mortgage securitization outstanding loan purchase and sold				$ 3,600	$ 3,800
Visa Class B Shares [Member]
Guarantor Obligations [Line Items]
Loss Contingency, Loss in Period		$ 7
[1]	Trading assets are primarily pledged against liabilities associated with repurchase agreements.

Guarantee Arrangements, Pledg_6

Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Summary of Credit Ratings of Credit Risk Related Guarantees (Detail) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2019		Dec. 31, 2018
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions		$ 63,121	[1]	$ 54,356
Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions		$ 54,256
Single name credit default swap [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Average Life in years	[2]	2 years 11 months 20 days
Credit Ratings of the Obligors or the Transactions	[2]	$ 40,688
Index credit derivatives [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Average Life in years	[2]	4 years 1 month 17 days
Credit Ratings of the Obligors or the Transactions	[2]	$ 12,233
Total return swaps [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Average Life in years	[2]	2 years 2 months 20 days
Credit Ratings of the Obligors or the Transactions	[2]	$ 1,335
Standby Letters of Credit [Member]
Credit Derivatives [Line Items]
Average Life in years	[1]	1 year 1 month 20 days
Credit Ratings of the Obligors or the Transactions	[1]	$ 8,865
External Credit Rating, Investment Grade [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[1]	41,042
External Credit Rating, Investment Grade [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions		33,857
External Credit Rating, Investment Grade [Member] | Single name credit default swap [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[2]	27,275
External Credit Rating, Investment Grade [Member] | Index credit derivatives [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[2]	5,509
External Credit Rating, Investment Grade [Member] | Total return swaps [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[2]	1,073
External Credit Rating, Investment Grade [Member] | Standby Letters of Credit [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[1]	7,185
External Credit Rating, Non Investment Grade [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[1]	22,079
External Credit Rating, Non Investment Grade [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions		20,399
External Credit Rating, Non Investment Grade [Member] | Single name credit default swap [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[2]	13,413
External Credit Rating, Non Investment Grade [Member] | Index credit derivatives [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[2]	6,724
External Credit Rating, Non Investment Grade [Member] | Total return swaps [Member] | Sell Protection Credit Derivatives [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[2]	262
External Credit Rating, Non Investment Grade [Member] | Standby Letters of Credit [Member]
Credit Derivatives [Line Items]
Credit Ratings of the Obligors or the Transactions	[1]	$ 1,680
[1]	External ratings for most of the obligors are not available. Presented above are the internal credit ratings which are developed using similar methodologies and rating scale equivalent to external credit ratings for purposes of classification as investment grade and non-investment grade.
[2]	The credit ratings in the table represent external credit ratings for classification as investment grade and non-investment grade.

Guarantee Arrangements, Pledg_7

Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Summary of Change in Estimated Repurchase Liability for Loans Sold to GSEs and Other Third Parties (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Estimated Repurchase Liability For Loans Sold [Roll Forward]
Decrease in liability recorded through earnings	$ 3,000,000	$ 16,000,000	$ 3,000,000	$ 510,000,000
Estimate of possible losses in excess of recorded liability	375,000,000		375,000,000
Obligation to Repurchase Receivables Sold [Member]
Estimated Repurchase Liability For Loans Sold [Roll Forward]
Balance at beginning of period	8,000,000	10,000,000	8,000,000	10,000,000
Decrease in liability recorded through earnings	(3,000,000)	(1,000,000)	(3,000,000)	(1,000,000)
Realized losses	(1,000,000)	0	(1,000,000)	0
Balance at end of period	4,000,000	$ 9,000,000	4,000,000	$ 9,000,000
Minimum [Member] | Obligation to Repurchase Receivables Sold [Member]
Estimated Repurchase Liability For Loans Sold [Roll Forward]
Estimate of possible losses in excess of recorded liability	0		0
Maximum [Member] | Obligation to Repurchase Receivables Sold [Member]
Estimated Repurchase Liability For Loans Sold [Roll Forward]
Estimate of possible losses in excess of recorded liability	$ 25,000,000		$ 25,000,000

Guarantee Arrangements, Pledg_8

Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Summary of Pledged Assets Included in Consolidated Balance Sheet (Detail) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Interest bearing deposits with banks		$ 2,762	$ 3,225
Trading assets	[1]	7,429	2,465
Securities available-for-sale	[2]	9,048	7,440
Securities held to maturity	[2]	2,718	1,747
Loans	[3]	17,371	18,189
Other assets	[4]	2,515	2,289
Total		$ 41,843	$ 35,355
[1]	Trading assets are primarily pledged against liabilities associated with repurchase agreements.
[2]	Securities are primarily pledged against derivatives, public fund deposits, trust deposits and various short-term and long term borrowings, as well as providing capacity for potential secured borrowings from the FHLB and the Federal Reserve Bank of New York.
[3]	Loans are primarily residential mortgage loans pledged against current and potential borrowings from the FHLB and the Federal Reserve Bank of New York.
[4]	Other assets represent cash on deposit with non-banks related to derivative collateral support agreements.

Guarantee Arrangements and Pled

Guarantee Arrangements and Pledged Assets and Repurchase Agreements - Offsetting of Resale and Repurchase Agreements and Securities Borrowing and Lending Agreements (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Securities purchased under agreements to resell, Gross Amounts Recognized		$ 11,602	$ 12,035
Securities purchased under agreements to resell, Gross Amounts Offset in the Balance Sheet	[1]	6,313	1,867
Securities Purchased under Agreements to Resell		5,289	10,168
Securities purchased under agreements to resell, Gross Amounts Not Offset in the Balance Sheet, Financial Instruments	[2]	5,287	10,165
Securities purchased under agreements to resell, Gross Amounts Not Offset in the Balance Sheet, Cash Collateral Receive / Pledged		0	0
Securities purchased under agreements to resell, Net amount	[3]	2	3
Securities sold under repurchase agreements, Gross Amounts Recognized		9,866	3,333
Securities sold under repurchase agreements, Gross Amounts Offset in the Balance Sheet	[1]	6,313	1,867
Securities sold under repurchase agreements, Net Amounts Presented in the Balance Sheet		3,553	1,466
Securities sold under repurchase agreements, Gross Amounts Not Offset in the Balance sheet, Financial Instruments	[2]	3,553	1,458
Securities sold under repurchase agreements, Gross Amounts Not Offset in the Balance Sheet, Cash Collateral Received / Pledged		0	0
Securities sold under repurchase agreements, Net amount	[3]	$ 0	$ 8
[1]	Represents recognized amount of resale and repurchase agreements with counterparties subject to legally enforceable netting agreements that meet the applicable netting criteria as permitted by generally accepted accounting principles.
[2]	Represents securities received or pledged to cover financing transaction exposures.
[3]	Represents the amount of our exposure that is not collateralized / covered by pledged collateral.

Guarantee Arrangements, Pledg_9

Guarantee Arrangements, Pledged Assets and Repurchase Agreements, Collateral Pledged and Remaining Contractual Maturity of Repurchase Agreements Accounted for as Secured Borrowings (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	$ 9,866
Maturity Overnight and Continuous [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	7,075
Maturity up to 30 Days [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	1,791
Maturity 31 to 90 Days [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	0
Maturity 91 Days to One Year [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	500
Maturity Greater than One Year [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	500
U.S. Treasury, U.S. Government agencies and sponsored entities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	9,719	$ 3,333
U.S. Treasury, U.S. Government agencies and sponsored entities [Member] | Maturity Overnight and Continuous [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	7,075	1,773
U.S. Treasury, U.S. Government agencies and sponsored entities [Member] | Maturity up to 30 Days [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	1,644	369
U.S. Treasury, U.S. Government agencies and sponsored entities [Member] | Maturity 31 to 90 Days [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	0	0
U.S. Treasury, U.S. Government agencies and sponsored entities [Member] | Maturity 91 Days to One Year [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	500	191
U.S. Treasury, U.S. Government agencies and sponsored entities [Member] | Maturity Greater than One Year [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	500	$ 1,000
Foreign debt securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	147
Foreign debt securities [Member] | Maturity Overnight and Continuous [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	0
Foreign debt securities [Member] | Maturity up to 30 Days [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	147
Foreign debt securities [Member] | Maturity 31 to 90 Days [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	0
Foreign debt securities [Member] | Maturity 91 Days to One Year [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	0
Foreign debt securities [Member] | Maturity Greater than One Year [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings	$ 0

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Recorded at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions		Jun. 30, 2019		Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Netting, Assets	[1],[2]	$ (24,555)		$ (25,172)
Netting Liabilities	[1],[2]	(24,555)		(25,172)
Trading assets		33,502		21,978
Trading liabilities		4,026		3,643
Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Trading assets		2,747		751
Precious metals [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Trading assets		3,895		1,889
Trading liabilities		106		215
Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Trading liabilities		3,086		2,690
Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Trading assets		3,045		3,048
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		99,332		81,030
Netting, Assets	[3]	(27,994)		(27,192)
Net Balance, Assets		71,338		53,838
Gross Balance, Liabilities		53,059		52,587
Netting Liabilities	[3]	(28,182)		(28,847)
Net Balance, Liabilities		24,877		23,740
Fair Value, Recurring [Member] | Domestic Deposits [Member] | Domestic Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		8,455	[4]	8,154
Net Balance, Liabilities		8,455	[4]	8,154
Fair Value, Recurring [Member] | Trading liabilities, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		940		953
Net Balance, Liabilities		940		953
Fair Value, Recurring [Member] | Derivative financial liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	31,463		31,671
Netting Liabilities	[3],[4]	(28,182)		(28,847)
Net Balance, Liabilities	[4]	3,281		2,824
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	12,804		11,185
Netting Liabilities	[3],[4]	0		0
Net Balance, Liabilities	[4]	12,804		11,185
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	13,052		15,733
Netting Liabilities	[3],[4]	0		0
Net Balance, Liabilities	[4]	13,052		15,733
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	2,901		2,866
Netting Liabilities	[3],[4]	0		0
Net Balance, Liabilities	[4]	2,901		2,866
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	1,391		900
Netting Liabilities	[3],[4]	0		0
Net Balance, Liabilities	[4]	1,391		900
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	1,275		947
Netting Liabilities	[3],[4]	0		0
Net Balance, Liabilities	[4]	1,275		947
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4],[5]	40		40
Netting Liabilities	[3],[4]	0		0	[5]
Net Balance, Liabilities	[4],[5]	40		40
Fair Value, Recurring [Member] | Derivative financial liabilities [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Netting Liabilities	[3],[4]	(28,182)		(28,847)
Net Balance, Liabilities	[4]	(28,182)		(28,847)
Fair Value, Recurring [Member] | Short-term borrowings [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		222		560	[4]
Net Balance, Liabilities		222		560	[4]
Fair Value, Recurring [Member] | Long-term Debt [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		11,979		11,249
Net Balance, Liabilities		11,979		11,249
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		10,698		5,520
Net Balance, Assets		10,698		5,520
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		86		100
Net Balance, Assets		86		100
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		16		16
Net Balance, Assets		16		16
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		90		92
Net Balance, Assets		90		92
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Corporate and other domestic debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		510		1,803
Net Balance, Assets		510		1,803
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		12,415		8,759
Net Balance, Assets		12,415		8,759
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		2,747		751
Net Balance, Assets		2,747		751
Fair Value, Recurring [Member] | Trading assets, excluding derivatives [Member] | Precious metals [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		3,895		1,889
Net Balance, Assets		3,895		1,889
Fair Value, Recurring [Member] | Derivative financial assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	31,190		30,330
Netting, Assets	[3],[4]	(27,994)		(27,192)
Net Balance, Assets	[4]	3,196		3,138
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	11,560		10,057
Netting, Assets	[3],[4]	0		0
Net Balance, Assets	[4]	11,560		10,057
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	13,370		15,921
Netting, Assets	[3],[4]	0		0
Net Balance, Assets	[4]	13,370		15,921
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	3,776		2,546
Netting, Assets	[3],[4]	0		0
Net Balance, Assets	[4]	3,776		2,546
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	1,360		845
Netting, Assets	[3],[4]	0		0
Net Balance, Assets	[4]	1,360		845
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	1,119		956
Netting, Assets	[3],[4]	0		0
Net Balance, Assets	[4]	1,119		956
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4],[5]	5		5
Netting, Assets	[3],[4],[5]	0		0
Net Balance, Assets	[4],[5]	5		5
Fair Value, Recurring [Member] | Derivative financial assets [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	0		0
Netting, Assets	[3],[4]	(27,994)		(27,192)
Net Balance, Assets	[4]	(27,994)		(27,192)
Fair Value, Recurring [Member] | Securities available-for-sale [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	34,130		27,897
Net Balance, Assets	[6]	34,130		27,897
Fair Value, Recurring [Member] | Securities available-for-sale [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	2,975		3,333
Net Balance, Assets	[6]	2,975		3,333
Fair Value, Recurring [Member] | Securities available-for-sale [Member] | Home Equity Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	36		42
Net Balance, Assets	[6]	36		42
Fair Value, Recurring [Member] | Securities available-for-sale [Member] | Other asset-backed securities available-for-sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	113		107
Net Balance, Assets	[6]	113		107
Fair Value, Recurring [Member] | Loans [Member] | Loans Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		128		109
Net Balance, Assets		128		109
Fair Value, Recurring [Member] | Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[7]	1		4
Net Balance, Assets	[7]	1		4
Fair Value, Recurring [Member] | Other assets [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		193		190	[6]
Net Balance, Assets		193		190	[6]
Fair Value, Recurring [Member] | Other assets [Member] | Equity Securities Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[8]	109		88
Net Balance, Assets	[8]	109		88
Fair Value, Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		47,938		33,249
Gross Balance, Liabilities		1,022		1,072
Fair Value, Recurring [Member] | Level 1 [Member] | Domestic Deposits [Member] | Domestic Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		0	[4]	0
Fair Value, Recurring [Member] | Level 1 [Member] | Trading liabilities, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		834		738
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	188		334
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	51		45
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		15
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	137		274
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4],[5]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial liabilities [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Short-term borrowings [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		0		0	[4]
Fair Value, Recurring [Member] | Level 1 [Member] | Long-term Debt [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		10,620		5,368
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Corporate and other domestic debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		12,199		8,552
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		2,747		751
Fair Value, Recurring [Member] | Level 1 [Member] | Trading assets, excluding derivatives [Member] | Precious metals [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	222		18
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	99		2
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	1		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	16		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	106		16
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4],[5]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Derivative financial assets [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Securities available-for-sale [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	19,559		16,198
Fair Value, Recurring [Member] | Level 1 [Member] | Securities available-for-sale [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	2,591		2,362
Fair Value, Recurring [Member] | Level 1 [Member] | Securities available-for-sale [Member] | Home Equity Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Securities available-for-sale [Member] | Other asset-backed securities available-for-sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Loans [Member] | Loans Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[7]	0		0
Fair Value, Recurring [Member] | Level 1 [Member] | Other assets [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0	[6]
Fair Value, Recurring [Member] | Level 1 [Member] | Other assets [Member] | Equity Securities Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[8]	0		0
Fair Value, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		50,193		45,392
Gross Balance, Liabilities		50,472		49,965
Fair Value, Recurring [Member] | Level 2 [Member] | Domestic Deposits [Member] | Domestic Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		7,525	[4]	7,229
Fair Value, Recurring [Member] | Level 2 [Member] | Trading liabilities, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		106		215
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	31,081		31,124
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	12,752		11,140
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	13,044		15,715
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	2,778		2,717
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	1,254		626
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	1,253		926
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4],[5]	0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial liabilities [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Short-term borrowings [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		222		560	[4]
Fair Value, Recurring [Member] | Level 2 [Member] | Long-term Debt [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		11,538		10,837
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		78		152
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Corporate and other domestic debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		216		207
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Trading assets, excluding derivatives [Member] | Precious metals [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		3,895		1,889
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	30,692		30,133
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	11,450		10,053
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	13,362		15,919
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	3,575		2,449
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	1,254		829
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	1,051		883
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4],[5]	0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Derivative financial assets [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Securities available-for-sale [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	14,571		11,699
Fair Value, Recurring [Member] | Level 2 [Member] | Securities available-for-sale [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	384		971
Fair Value, Recurring [Member] | Level 2 [Member] | Securities available-for-sale [Member] | Home Equity Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	36		42
Fair Value, Recurring [Member] | Level 2 [Member] | Securities available-for-sale [Member] | Other asset-backed securities available-for-sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Loans [Member] | Loans Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		128		109
Fair Value, Recurring [Member] | Level 2 [Member] | Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[7]	0		0
Fair Value, Recurring [Member] | Level 2 [Member] | Other assets [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		193		190	[6]
Fair Value, Recurring [Member] | Level 2 [Member] | Other assets [Member] | Equity Securities Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[8]	0		0
Fair Value, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		1,092		2,301
Gross Balance, Liabilities		1,565		1,550
Fair Value, Recurring [Member] | Level 3 [Member] | Domestic Deposits [Member] | Domestic Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		930	[4]	925
Fair Value, Recurring [Member] | Level 3 [Member] | Trading liabilities, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	194		213
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	1		0
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	8		3
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	123		149
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	22		21
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4],[5]	40		40
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial liabilities [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities	[4]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Short-term borrowings [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		0		0	[4]
Fair Value, Recurring [Member] | Level 3 [Member] | Long-term Debt [Member] | Long-term debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Liabilities		441		412
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Collateralized debt obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		86		100
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		16		16
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		90		92
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Corporate and other domestic debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		510		1,803
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member] | Precious metals [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	276		179
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	11		2
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	7		2
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Equity contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	185		97
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Precious metals contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Credit contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	68		73
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Other Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4],[5]	5		5
Fair Value, Recurring [Member] | Level 3 [Member] | Derivative financial assets [Member] | Derivatives netting [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[4]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Securities available-for-sale [Member] | U.S. Treasury, U.S. Government agencies and sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Securities available-for-sale [Member] | Foreign debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Securities available-for-sale [Member] | Home Equity Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Securities available-for-sale [Member] | Other asset-backed securities available-for-sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[6]	113		107
Fair Value, Recurring [Member] | Level 3 [Member] | Loans [Member] | Loans Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0
Fair Value, Recurring [Member] | Level 3 [Member] | Other assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[7]	1		4
Fair Value, Recurring [Member] | Level 3 [Member] | Other assets [Member] | Equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets		0		0	[6]
Fair Value, Recurring [Member] | Level 3 [Member] | Other assets [Member] | Equity Securities Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Gross Balance, Assets	[8]	$ 0		$ 0
[1]	Netting is performed at a counterparty level in cases where enforceable master netting agreements are in place, regardless of the type of derivative instrument. Therefore, we have not allocated netting to the different types of derivative instruments shown in the table above.
[2]	Represents the netting of derivative receivable and payable balances for the same counterparty under enforceable netting agreements.
[3]	Represents counterparty and cash collateral netting which allow the offsetting of amounts relating to certain contracts if certain conditions are met.
[4]	Includes trading derivative assets of $3,045 million and $3,048 million and trading derivative liabilities of $3,086 million and $2,690 million at June 30, 2019 and December 31, 2018, respectively, as well as derivatives held for hedging and commitments accounted for as derivatives. See Note 9, "Derivative Financial Instruments," for additional information. Excluding changes in fair value of a derivative instrument associated with a qualifying cash flow hedge, which are recognized initially in other comprehensive income (loss), derivative assets and liabilities are recorded at fair value through net income
[5]	Consists of swap agreements entered into in conjunction with the sales of Visa Class B Shares.
[6]	Securities available-for-sale are recorded at fair value through other comprehensive income (loss).
[7]	Represents contingent consideration receivable associated with the sale of a portion of our PB business.
[8]	Investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy.

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Fair Value of Level 3 Assets and Liabilities (Detail) - Level 3 [Member] - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2019		Jun. 30, 2018		Jun. 30, 2019		Jun. 30, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance		$ 867		$ 2,152		$ 2,088		$ 2,207
Fair Value Assets, Gains (Losses) Included In Earnings		43		(24)		82		(58)
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income		4		0		6		(4)
Fair Value Assets, Purchases		0		0		0		0
Fair Value Assets, Issuances		0		0		0		0
Fair Value Assets, Settlements		(9)		(16)		(1,272)		(33)
Fair Value Assets, Transfers Into Level 3		0		(1)		0		(1)
Fair Value Assets, Transfers Out of Level 3		(7)		2		(6)		2
Fair Value Assets, Ending Balance		898		2,113		898		2,113
Fair Value Assets, Current Period Unrealized Gains (Losses)		36		(10)		115		(46)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Liability, Beginning Balance		(1,402)		(1,546)		(1,337)		(1,538)
Fair Value Liability, Gains (Losses) Included In Earnings		(50)		(3)		(107)		29
Fair Value, Liability, Gains (Losses) Included in Other Comprehensive Income		3		6		(5)		8
Fair Value Liability, Purchases		0		0		0		0
Fair Value Liability, Issuances		(82)		(116)		(209)		(322)
Fair Value Liability, Settlements		84		112		142		201
Fair Value Liability, Transfers Into Level 3		(5)		(10)		(5)		(13)
Fair Value Liability, Transfers Out of Level 3		81		124		150		202
Fair Value Liability, Ending Balance		(1,371)		(1,433)		(1,371)		(1,433)
Fair Value Liability, Current Period Unrealized Gains (Losses)		(39)		9		(196)		43
Interest rate contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Derivatives, net, Beginning Balance	[1]	7				2
Derivatives, net, Gains (Losses) included in Earnings	[1]	8				13
Derivatives, net, Gains (Losses) included in Other Comprehensive Income	[1]	0				0
Derivatives, net, Purchases	[1]	0				0
Derivatives, net, Issuances	[1]	0				0
Derivatives, net, Settlements	[1]	0				0
Derivatives, net, Transfers into Level 3	[1]	0				0
Derivatives, net, Transfers out of Level 3	[1]	(5)				(5)
Derivatives, net, Ending Balance	[1]	10				10
Derivatives, net, Current Period Unrealized Gains (Losses)	[1]	3				8
Foreign exchange contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Derivatives, net, Beginning Balance	[1]	(1)		0		(1)	[2]	0
Derivatives, net, Gains (Losses) included in Earnings	[1]	0		(1)		0		(1)
Derivatives, net, Gains (Losses) included in Other Comprehensive Income	[1]	0		0		0		0
Derivatives, net, Purchases	[1]	0		0		0		0
Derivatives, net, Issuances	[1]	0		0		0		0
Derivatives, net, Settlements	[1]	0		0		0		0
Derivatives, net, Transfers into Level 3	[1]	0		0		0		0
Derivatives, net, Transfers out of Level 3	[1]	0		0		0		0
Derivatives, net, Ending Balance	[1]	(1)	[2]	(1)		(1)	[2]	(1)
Derivatives, net, Current Period Unrealized Gains (Losses)	[1]	0		(1)		0		(1)
Equity contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Derivatives, net, Beginning Balance	[1]	24		27		(52)	[2]	81
Derivatives, net, Gains (Losses) included in Earnings	[1]	39		(10)		110		(50)
Derivatives, net, Gains (Losses) included in Other Comprehensive Income	[1]	0		0		0		0
Derivatives, net, Purchases	[1]	0		0		0		0
Derivatives, net, Issuances	[1]	0		0		0		0
Derivatives, net, Settlements	[1]	1		(16)		5		(30)
Derivatives, net, Transfers into Level 3	[1]	0		(1)		0		(1)
Derivatives, net, Transfers out of Level 3	[1]	(2)		2		(1)		2
Derivatives, net, Ending Balance	[1]	62	[2]	2		62	[2]	2
Derivatives, net, Current Period Unrealized Gains (Losses)	[1]	40		(7)		115		(45)
Credit contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Derivatives, net, Beginning Balance	[1]	53		113		52		114
Derivatives, net, Gains (Losses) included in Earnings	[1]	(3)		1		(40)		2
Derivatives, net, Gains (Losses) included in Other Comprehensive Income	[1]	0		0		0		0
Derivatives, net, Purchases	[1]	0		0		0		0
Derivatives, net, Issuances	[1]	0		0		0		0
Derivatives, net, Settlements	[1]	(4)		(4)		34		(6)
Derivatives, net, Transfers into Level 3	[1]	0		0		0		0
Derivatives, net, Transfers out of Level 3	[1]	0		0		0		0
Derivatives, net, Ending Balance	[1]	46		110		46		110
Derivatives, net, Current Period Unrealized Gains (Losses)	[1]	(2)		(3)		(2)		(4)
Other Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Derivatives, net, Beginning Balance	[1]	(37)		(44)		(35)		(46)
Derivatives, net, Gains (Losses) included in Earnings	[1]	(3)		(12)		(9)		(14)
Derivatives, net, Gains (Losses) included in Other Comprehensive Income	[1]	0		0		0		0
Derivatives, net, Purchases	[1]	0		0		0		0
Derivatives, net, Issuances	[1]	0		0		0		0
Derivatives, net, Settlements	[1]	5		5		9		9
Derivatives, net, Transfers into Level 3	[1]	0		0		0		0
Derivatives, net, Transfers out of Level 3	[1]	0		0		0		0
Derivatives, net, Ending Balance	[1]	(35)		(51)		(35)		(51)
Derivatives, net, Current Period Unrealized Gains (Losses)	[1]	0		0		0		0
Domestic Deposits [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Liability, Beginning Balance	[3]	(949)		(916)		(925)	[2],[4]	(897)
Fair Value Liability, Gains (Losses) Included In Earnings	[3]	(35)		2		(64)		23
Fair Value, Liability, Gains (Losses) Included in Other Comprehensive Income	[3]	2		5		(3)		3
Fair Value Liability, Purchases	[3]	0		0		0		0
Fair Value Liability, Issuances	[3]	(49)		(88)		(145)		(179)
Fair Value Liability, Settlements	[3]	64		38		109		60
Fair Value Liability, Transfers Into Level 3	[3]	(5)		(10)		(5)		(13)
Fair Value Liability, Transfers Out of Level 3	[3]	42		93		103		127
Fair Value Liability, Ending Balance	[3]	(930)	[2],[4]	(876)		(930)	[2],[4]	(876)
Fair Value Liability, Current Period Unrealized Gains (Losses)	[3]	(30)		8		(135)		25
Long-term debt [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Liability, Beginning Balance	[3]	(453)		(630)		(412)	[2],[4]	(641)
Fair Value Liability, Gains (Losses) Included In Earnings	[3]	(15)		(5)		(43)		6
Fair Value, Liability, Gains (Losses) Included in Other Comprehensive Income	[3]	1		1		(2)		5
Fair Value Liability, Purchases	[3]	0		0		0		0
Fair Value Liability, Issuances	[3]	(33)		(28)		(64)		(143)
Fair Value Liability, Settlements	[3]	20		74		33		141
Fair Value Liability, Transfers Into Level 3	[3]	0		0		0		0
Fair Value Liability, Transfers Out of Level 3	[3]	39		31		47		75
Fair Value Liability, Ending Balance	[3]	(441)	[2],[4]	(557)		(441)	[2],[4]	(557)
Fair Value Liability, Current Period Unrealized Gains (Losses)	[3]	(9)		1		(61)		18
Trading assets, excluding derivatives [Member] | Collateralized debt obligations [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance	[5]	90		131		100		129
Fair Value Assets, Gains (Losses) Included In Earnings	[5]	2		1		3		8
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income	[5]	0		0		0		0
Fair Value Assets, Purchases	[5]	0		0		0		0
Fair Value Assets, Issuances	[5]	0		0		0		0
Fair Value Assets, Settlements	[5]	(6)		(1)		(17)		(6)
Fair Value Assets, Transfers Into Level 3	[5]	0		0		0		0
Fair Value Assets, Transfers Out of Level 3	[5]	0		0		0		0
Fair Value Assets, Ending Balance	[5]	86		131		86		131
Fair Value Assets, Current Period Unrealized Gains (Losses)	[5]	(4)		1		(10)		8
Trading assets, excluding derivatives [Member] | Residential mortgage asset-backed securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance		16				16	[5]
Fair Value Assets, Gains (Losses) Included In Earnings		0				0	[5]
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income	[5]	0				0
Fair Value Assets, Purchases		0				0	[5]
Fair Value Assets, Issuances		0				0	[5]
Fair Value Assets, Settlements		0				0	[5]
Fair Value Assets, Transfers Into Level 3		0				0
Fair Value Assets, Transfers Out of Level 3		0				0	[5]
Fair Value Assets, Ending Balance	[5]	16				16
Fair Value Assets, Current Period Unrealized Gains (Losses)		0				0	[5]
Trading assets, excluding derivatives [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance		95				92
Fair Value Assets, Gains (Losses) Included In Earnings		0				5	[5]
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income		0	[5]			0
Fair Value Assets, Purchases		0				0
Fair Value Assets, Issuances		0				0
Fair Value Assets, Settlements		(5)				(7)
Fair Value Assets, Transfers Into Level 3		0				0
Fair Value Assets, Transfers Out of Level 3		0				0
Fair Value Assets, Ending Balance		90				90
Fair Value Assets, Current Period Unrealized Gains (Losses)		(5)				(2)
Trading assets, excluding derivatives [Member] | Corporate and other domestic debt securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance		510	[5]	1,803	[5]	1,803		1,803	[5]
Fair Value Assets, Gains (Losses) Included In Earnings	[5]	0		0		0		0
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income		0	[5]	0	[5]	0		0	[5]
Fair Value Assets, Purchases		0	[5]	0	[5]	0		0	[5]
Fair Value Assets, Issuances		0	[5]	0	[5]	0		0	[5]
Fair Value Assets, Settlements		0	[5]	0	[5]	(1,293)		0	[5]
Fair Value Assets, Transfers Into Level 3		0	[5]	0	[5]	0		0	[5]
Fair Value Assets, Transfers Out of Level 3		0	[5]	0	[5]	0		0	[5]
Fair Value Assets, Ending Balance	[5]	510		1,803		510		1,803
Fair Value Assets, Current Period Unrealized Gains (Losses)		0	[5]	0	[5]	0		0	[5]
Available-for-sale securities [Member] | Other asset-backed securities available-for-sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance	[6]	109		107		107		111
Fair Value Assets, Gains (Losses) Included In Earnings	[6]	0		0		0		0
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income		4	[6]	0	[1]	6	[6]	(4)	[6]
Fair Value Assets, Purchases	[6]	0		0		0		0
Fair Value Assets, Issuances	[6]	0		0		0		0
Fair Value Assets, Settlements	[6]	0		0		0		0
Fair Value Assets, Transfers Into Level 3	[6]	0		0		0		0
Fair Value Assets, Transfers Out of Level 3	[6]	0		0		0		0
Fair Value Assets, Ending Balance	[6]	113		107		113		107
Fair Value Assets, Current Period Unrealized Gains (Losses)	[6]	4		0		6		(4)
Other assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value Assets, Beginning Balance	[7]	1		15		4		15
Fair Value Assets, Gains (Losses) Included In Earnings	[7]	0		(3)		0		(3)
Fair Value Assets, Gains (Losses) Included in Other Comprehensive Income	[7]	0		0		0		0
Fair Value Assets, Purchases	[7]	0		0		0		0
Fair Value Assets, Issuances	[7]	0		0		0		0
Fair Value Assets, Settlements	[7]	0		0		(3)		0
Fair Value Assets, Transfers Into Level 3	[7]	0		0		0		0
Fair Value Assets, Transfers Out of Level 3	[7]	0		0		0		0
Fair Value Assets, Ending Balance	[7]	1		12		1		12
Fair Value Assets, Current Period Unrealized Gains (Losses)	[7]	$ 0		$ 0		$ 0		$ 0
[1]	Level 3 net derivatives included derivative assets of $276 million and derivative liabilities of $194 million at June 30, 2019 and derivative assets of $253 million and derivative liabilities of $193 million at June 30, 2018. Gains (losses) on derivatives, net are predominantly included in trading revenue and gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income.
[2]	We are the client-facing entity and we enter into identical but opposite derivatives to transfer the resultant risks to our affiliates. With the exception of counterparty credit risks, we are market neutral. The corresponding intra-group derivatives are presented as equity derivatives and foreign exchange derivatives in the table.
[3]	Excluding unrealized gains (losses) on fair value option liabilities attributable to our own credit spread, which are recorded in other comprehensive income (loss), gains (losses) on fair value option liabilities are included in gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income.
[4]	Structured deposits and structured notes contain embedded derivative features whose fair value measurements contain significant Level 3 inputs.
[5]	Gains (losses) on trading assets, excluding derivatives are included in trading revenue in the consolidated statement of income.
[6]	Realized gains (losses) on securities available-for-sale are included in other securities gains, net in the consolidated statement of income. Unrealized gains (losses) on securities available-for-sale are included in other comprehensive income (loss).
[7]	Represents contingent consideration receivable associated with the sale of a portion of our PB business. Gains (losses) associated with this transaction are included in other income (loss) in the consolidated statement of income.

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative Information about Recurring Fair Value Measurement of Assets and Liabilities Classified as Level 3 (Detail) $ in Millions		6 Months Ended		12 Months Ended
		Jun. 30, 2019USD ($)		Dec. 31, 2018USD ($)		Mar. 31, 2019USD ($)		Jun. 30, 2018USD ($)		Mar. 31, 2018USD ($)		Dec. 31, 2017USD ($)
Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		$ 898		$ 2,088		$ 867		$ 2,113		$ 2,152		$ 2,207
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value		1,371		1,337		1,402		1,433		1,546		1,538
Deposits [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	[1]	930	[2],[3]	925	[2],[3]	949		876		916		897
Borrowings [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	[1]	441	[2],[3]	412	[2],[3]	453		557		630		641
Credit contracts [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	[4]	46		52		53		110		113		114
Equity contracts [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	[4]	62	[3]	(52)	[3]	24		2		27		81
Foreign exchange contracts [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	[4]	(1)	[3]	(1)	[3]	(1)		(1)		0		0
Interest rate contracts [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	[4]	10		2		7
Other Contracts [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	[4]	(35)		(35)		(37)		(51)		(44)		(46)
Trading assets, excluding derivatives [Member] | Collateralized debt obligations [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	[5]	86		100		90		131		131		129
Trading assets, excluding derivatives [Member] | Residential mortgage asset-backed securities [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		16	[5]	16	[5]	16
Trading assets, excluding derivatives [Member] | Student loan asset-backed securities [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		90		92		95
Trading assets, excluding derivatives [Member] | Corporate and other domestic debt securities [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		510	[5]	1,803		510	[5]	1,803	[5]	1,803	[5]	1,803	[5]
Available-for-sale securities [Member] | Other asset-backed securities available-for-sale [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	[6]	113		107		109		107		107		111
Other assets [Member] | Level 3 [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	[7]	$ 1		$ 4		$ 1		$ 12		$ 15		$ 15
Measurement Input, Prepayment Rates [Member] | Collateralized debt obligations [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0		0
Measurement Input, Prepayment Rates [Member] | Collateralized debt obligations [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.01		0.01
Measurement Input, Prepayment Rates [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.05		0
Measurement Input, Prepayment Rates [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.10		0.05
Measurement Input, Prepayment Rates [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.07		0.06
Measurement Input, Prepayment Rates [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.09		0.07
Measurement Input, Default Rates [Member] | Collateralized debt obligations [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0		0
Measurement Input, Default Rates [Member] | Collateralized debt obligations [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.01		0.01
Measurement Input, Default Rates [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.01		0.01
Measurement Input, Default Rates [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.05		0.04
Measurement Input, Default Rates [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0		0.01
Measurement Input, Default Rates [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.01		0.02
Measurement Input, Loss Severity Rates [Member] | Collateralized debt obligations [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.90		0.90
Measurement Input, Loss Severity Rates [Member] | Collateralized debt obligations [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.95		0.95
Measurement Input, Loss Severity Rates [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.65		0.80
Measurement Input, Loss Severity Rates [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.70		0.85
Measurement Input, Loss Severity Rates [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.25		0.25
Measurement Input, Loss Severity Rates [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.40		0.40
Measurement Input, Discount Margin [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.0100		0.0100
Measurement Input, Discount Margin [Member] | Residential mortgage asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.0250		0.0250
Measurement Input, Discount Margin [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.0095		0.0091
Measurement Input, Discount Margin [Member] | Student loan asset-backed securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Broker Quotes or Consensus Pricing [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.0198		0.0115
Measurement Input, Spread Volatility on Collateral Assets [Member] | Corporate and other domestic debt securities [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.02		0.02
Measurement Input, Spread Volatility on Collateral Assets [Member] | Corporate and other domestic debt securities [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.04		0.04
Measurement Input, Correlation between Insurance Claim Shortfall and Collateral Value [Member] | Corporate and other domestic debt securities [Member] | Recurring [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Trading, Measurement Input		0.80		0.80
Measurement Input, Probability to Fund for Rate Lock Commitments [Member] | Interest rate contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Market Comparable Adjusted for Probability to Fund [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.38		0.03
Measurement Input, Probability to Fund for Rate Lock Commitments [Member] | Interest rate contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Market Comparable Adjusted for Probability to Fund [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.96		0.99
Measurement Input, Interest Rate Transaction Execution [Member] | Interest rate contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Market Comparable Adjusted for Probability to Fund [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.75		0.75
Measurement Input, Interest Rate Transaction Execution [Member] | Interest rate contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Market Comparable Adjusted for Probability to Fund [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		1		1
Measurement Input, Implied Volatility of Currency Pairs [Member] | Deposits [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Domestic Deposits, Measurement Input	[2],[3]	0.09		0.08
Measurement Input, Implied Volatility of Currency Pairs [Member] | Deposits [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Domestic Deposits, Measurement Input	[2],[3]	0.13		0.12
Measurement Input, Implied Volatility of Currency Pairs [Member] | Borrowings [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Long-term Debt, Measurement Input	[2],[3]	0.09		0.08
Measurement Input, Implied Volatility of Currency Pairs [Member] | Borrowings [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Long-term Debt, Measurement Input	[2],[3]	0.13		0.12
Measurement Input, Implied Volatility of Currency Pairs [Member] | Foreign exchange contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.09		0.08
Measurement Input, Implied Volatility of Currency Pairs [Member] | Foreign exchange contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.13		0.12
Measurement Input, Equity / Equity Index Volatility [Member] | Deposits [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Domestic Deposits, Measurement Input	[2],[3]	0.07		0.07
Measurement Input, Equity / Equity Index Volatility [Member] | Deposits [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Domestic Deposits, Measurement Input	[2],[3]	0.29		0.37
Measurement Input, Equity / Equity Index Volatility [Member] | Borrowings [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Long-term Debt, Measurement Input	[2],[3]	0.07		0.07
Measurement Input, Equity / Equity Index Volatility [Member] | Borrowings [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Long-term Debt, Measurement Input	[2],[3]	0.33		0.42
Measurement Input, Equity / Equity Index Volatility [Member] | Equity contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.07		0.07
Measurement Input, Equity / Equity Index Volatility [Member] | Equity contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.38		0.44
Measurement Input, Equity/Equity and Equity/Index Correlation [Member] | Deposits [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Domestic Deposits, Measurement Input		0.43		0.42
Measurement Input, Equity/Equity and Equity/Index Correlation [Member] | Deposits [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Domestic Deposits, Measurement Input		0.46		0.49
Measurement Input, Equity/Equity and Equity/Index Correlation [Member] | Borrowings [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Long-term Debt, Measurement Input	[2],[3]	0.26		0.45
Measurement Input, Equity/Equity and Equity/Index Correlation [Member] | Borrowings [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Adjusted Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Long-term Debt, Measurement Input	[2],[3]	0.79		0.79
Measurement Input, Equity/Equity and Equity/Index Correlation [Member] | Equity contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.26		0.42
Measurement Input, Equity/Equity and Equity/Index Correlation [Member] | Equity contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.79		0.79
Measurement Input, Equity Dividend Yields [Member] | Equity contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0		0
Measurement Input, Equity Dividend Yields [Member] | Equity contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[3]	0.04		0.07
Measurement Input, Credit Default Swap Spreads [Member] | Credit contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.0049		0.0102
Measurement Input, Credit Default Swap Spreads [Member] | Credit contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Option Pricing Model [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0.0063		0.0118
Measurement Input, Conversion Rate [Member] | Other Contracts [Member] | Recurring [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		1.6		1.6
Measurement Input, Expected Duration [Member] | Other Contracts [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Contract, Duration, Measurement Input		1 year		2 years
Measurement Input, Expected Duration [Member] | Other Contracts [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Derivative Contract, Duration, Measurement Input		2 years		3 years
Measurement Input, Market Assumptions Related to Yields for Comparable Instruments [Member] | Other asset-backed securities available-for-sale [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.01		0.01
Measurement Input, Market Assumptions Related to Yields for Comparable Instruments [Member] | Other asset-backed securities available-for-sale [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.03		0.03
Measurement Input, Client Transfer Rates Based on Rating [Member] | Recurring [Member] | Minimum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Other Assets, Measurement Input		0.50		0.50
Measurement Input, Client Transfer Rates Based on Rating [Member] | Recurring [Member] | Maximum [Member] | Valuation Technique, Discounted Cash Flows [Member]
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]
Other Assets, Measurement Input		0.95		0.95
[1]	Excluding unrealized gains (losses) on fair value option liabilities attributable to our own credit spread, which are recorded in other comprehensive income (loss), gains (losses) on fair value option liabilities are included in gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income.
[2]	Structured deposits and structured notes contain embedded derivative features whose fair value measurements contain significant Level 3 inputs.
[3]	We are the client-facing entity and we enter into identical but opposite derivatives to transfer the resultant risks to our affiliates. With the exception of counterparty credit risks, we are market neutral. The corresponding intra-group derivatives are presented as equity derivatives and foreign exchange derivatives in the table.
[4]	Level 3 net derivatives included derivative assets of $276 million and derivative liabilities of $194 million at June 30, 2019 and derivative assets of $253 million and derivative liabilities of $193 million at June 30, 2018. Gains (losses) on derivatives, net are predominantly included in trading revenue and gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income.
[5]	Gains (losses) on trading assets, excluding derivatives are included in trading revenue in the consolidated statement of income.
[6]	Realized gains (losses) on securities available-for-sale are included in other securities gains, net in the consolidated statement of income. Unrealized gains (losses) on securities available-for-sale are included in other comprehensive income (loss).
[7]	Represents contingent consideration receivable associated with the sale of a portion of our PB business. Gains (losses) associated with this transaction are included in other income (loss) in the consolidated statement of income.

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2019USD ($)		Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)		Jun. 30, 2018USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)		Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Deferred fees		$ 2			$ 2				$ 2
Revaluation period					90 days
Unfunded commitments, equity securities measured at net asset value		67			$ 67				72
Derivative financial assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 assets		276		$ 253	276		$ 253
Derivative financial liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 liabilities	[1]	194		193	194		193
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 assets		898		2,113	898		2,113	$ 867	2,088		$ 2,152	$ 2,207
Fair value of level 3 liabilities		1,371		1,433	1,371		1,433	1,402	1,337		1,546	1,538
Fair Value Assets, Transfers Into Level 3		0		(1)	0		(1)
Fair Value Assets, Transfers Out of Level 3		(7)		2	(6)		2
Fair Value Liability, Transfers Into Level 3		5		10	5		13
Fair Value Liability, Transfers Out of Level 3		81		124	150		202
Collateralized debt obligations [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 assets	[2]	86		131	86		131	90	100		131	129
Fair Value Assets, Transfers Into Level 3	[2]	0		0	0		0
Fair Value Assets, Transfers Out of Level 3	[2]	0		0	0		0
Domestic Deposits [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 liabilities	[1]	930	[3],[4]	876	930	[3],[4]	876	949	925	[3],[4]	916	897
Fair Value Liability, Transfers Into Level 3	[1]	5		10	5		13
Fair Value Liability, Transfers Out of Level 3	[1]	42		93	103		127
Borrowings [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 liabilities	[1]	441	[3],[4]	557	441	[3],[4]	557	453	412	[3],[4]	$ 630	$ 641
Fair Value Liability, Transfers Into Level 3	[1]	0		0	0		0
Fair Value Liability, Transfers Out of Level 3	[1]	39		$ 31	47		$ 75
Residential Mortgage Backed Securities [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 assets		16	[2]		16	[2]		16	16	[2]
Fair Value Assets, Transfers Into Level 3		0			0
Fair Value Assets, Transfers Out of Level 3		0			0	[2]
Student loan asset-backed securities [Member] | Level 3 [Member] | Trading assets, excluding derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of level 3 assets		90			90			$ 95	92
Fair Value Assets, Transfers Into Level 3		0			0
Fair Value Assets, Transfers Out of Level 3		0			0
Unfunded Loan Commitment [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Deferred fees		$ 157			$ 157				$ 165
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0			0				0
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.01			0.01				0.01
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.004			0.004
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.05			0.05				0
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.10			0.10				0.05
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.05			0.05
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.07			0.07				0.06
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.09			0.09				0.07
Measurement Input, Prepayment Rates [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.08			0.08
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0			0				0
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.01			0.01				0.01
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.009			0.009
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.01			0.01				0.01
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.05			0.05				0.04
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.05			0.05
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0			0				0.01
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.01			0.01				0.02
Measurement Input, Default Rate [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.008			0.008
Measurement Input, Implied Volatility of Currency Pairs [Member] | Fair Value, Recurring [Member] | Valuation Technique, Option Pricing Model [Member] | Foreign exchange contracts [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[4]	0.09			0.09				0.08
Measurement Input, Implied Volatility of Currency Pairs [Member] | Fair Value, Recurring [Member] | Valuation Technique, Option Pricing Model [Member] | Foreign exchange contracts [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[4]	0.13			0.13				0.12
Measurement Input, Implied Volatility of Currency Pairs [Member] | Fair Value, Recurring [Member] | Valuation Technique, Option Pricing Model [Member] | Foreign exchange contracts [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[4]	0.02			0.02
Measurement Input, Loss Severity Rates [Member] | Impaired commercial loans [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Loans Held-for-sale, Measurement Input		0.48			0.48
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.90			0.90				0.90
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.95			0.95				0.95
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Collateralized debt obligations [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.93			0.93
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.65			0.65				0.80
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.70			0.70				0.85
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.65			0.65
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.25			0.25				0.25
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.40			0.40				0.40
Measurement Input, Loss Severity Rates [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.36			0.36
Measurement Input, Discount Margin [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.0100			0.0100				0.0100
Measurement Input, Discount Margin [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.0250			0.0250				0.0250
Measurement Input, Discount Margin [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.0200			0.0200
Measurement Input, Discount Margin [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.0095			0.0095				0.0091
Measurement Input, Discount Margin [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.0198			0.0198				0.0115
Measurement Input, Discount Margin [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member] | Valuation Technique, Consensus Pricing Model [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Debt Securities, Trading, Measurement Input		0.0122			0.0122
Measurement Input, Equity / Equity Index Volatility [Member] | Fair Value, Recurring [Member] | Valuation Technique, Option Pricing Model [Member] | Equity contracts [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[4]	0.07			0.07				0.07
Measurement Input, Equity / Equity Index Volatility [Member] | Fair Value, Recurring [Member] | Valuation Technique, Option Pricing Model [Member] | Equity contracts [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[4]	0.38			0.38				0.44
Measurement Input, Equity / Equity Index Volatility [Member] | Fair Value, Recurring [Member] | Valuation Technique, Option Pricing Model [Member] | Equity contracts [Member] | Weighted Average [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset (Liability) Net, Measurement Input	[4]	0.06			0.06
[1]	Excluding unrealized gains (losses) on fair value option liabilities attributable to our own credit spread, which are recorded in other comprehensive income (loss), gains (losses) on fair value option liabilities are included in gain (loss) on instruments designated at fair value and related derivatives in the consolidated statement of income.
[2]	Gains (losses) on trading assets, excluding derivatives are included in trading revenue in the consolidated statement of income.
[3]	Structured deposits and structured notes contain embedded derivative features whose fair value measurements contain significant Level 3 inputs.
[4]	We are the client-facing entity and we enter into identical but opposite derivatives to transfer the resultant risks to our affiliates. With the exception of counterparty credit risks, we are market neutral. The corresponding intra-group derivatives are presented as equity derivatives and foreign exchange derivatives in the table.

Fair Value Measurements - Ass_2

Fair Value Measurements - Assets and Liabilities Recorded as Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018		Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Total Gains (Losses)		$ (2)	$ 46	$ (5)	$ 104
Residential Mortgage [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Total Gains (Losses)	[1]	0		0
Consumer loans [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Total Gains (Losses)	[2]	(2)	(1)	(4)	(2)
Commercial Loans Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Total Gains (Losses)			0		3	[3]
Impaired commercial loans [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Total Gains (Losses)	[4]	0	46	(1)	101
Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Total Gains (Losses)	[5]	0	$ 1	0	$ 2
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		52		52			$ 95
Fair Value, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		0		0			0
Fair Value, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		22		22			58
Fair Value, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		30		30			37
Fair Value, Nonrecurring [Member] | Residential Mortgage [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[1]	6		6
Fair Value, Nonrecurring [Member] | Residential Mortgage [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[1]	0		0
Fair Value, Nonrecurring [Member] | Residential Mortgage [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[1]	6		6
Fair Value, Nonrecurring [Member] | Residential Mortgage [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[1]	0		0
Fair Value, Nonrecurring [Member] | Consumer loans [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[2]	11		11			15
Fair Value, Nonrecurring [Member] | Consumer loans [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[2]	0		0			0
Fair Value, Nonrecurring [Member] | Consumer loans [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[2]	11		11			15
Fair Value, Nonrecurring [Member] | Consumer loans [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[2]	0		0			0
Fair Value, Nonrecurring [Member] | Commercial Loans Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[3]						36
Fair Value, Nonrecurring [Member] | Commercial Loans Held for Sale [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[3]						0
Fair Value, Nonrecurring [Member] | Commercial Loans Held for Sale [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[3]						36
Fair Value, Nonrecurring [Member] | Commercial Loans Held for Sale [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[3]						0
Fair Value, Nonrecurring [Member] | Impaired commercial loans [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[4]	30		30			37
Fair Value, Nonrecurring [Member] | Impaired commercial loans [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[4]	0		0			0
Fair Value, Nonrecurring [Member] | Impaired commercial loans [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[4]	0		0			0
Fair Value, Nonrecurring [Member] | Impaired commercial loans [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[4]	30		30			37
Fair Value, Nonrecurring [Member] | Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[5]	5		5			7
Fair Value, Nonrecurring [Member] | Real Estate Owned [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[5]	0		0			0
Fair Value, Nonrecurring [Member] | Real Estate Owned [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[5]	5		5			7
Fair Value, Nonrecurring [Member] | Real Estate Owned [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[5]	$ 0		$ 0			$ 0
[1]	At June 30, 2019, the fair value of the loans held for sale was below cost.
[2]	Represents residential mortgage loans held for investment whose carrying amount was reduced during the periods presented based on the fair value of the underlying collateral.
[3]	At December 31, 2018, the fair value of the loans held for sale was below cost.
[4]	Certain commercial loans have undergone troubled debt restructurings and are considered impaired. As a matter of practical expedient, we measure the credit impairment of a collateral-dependent loan based on the fair value of the collateral asset. The collateral often involves real estate properties that are illiquid due to market conditions. As a result, these loans are classified as a Level 3 fair value measurement within the fair value hierarchy.
[5]	Real estate owned is required to be reported on the balance sheet net of transactions costs. The real estate owned amounts in the table above reflect the fair value unadjusted for transaction costs.

Fair Value Measurements - Qua_2

Fair Value Measurements - Quantitative Information about Nonrecurring Fair Value Measurement of Assets and Liabilities Classified as Level 3 (Detail) $ in Millions		Jun. 30, 2019USD ($)		Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)		Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		$ 898		$ 867	$ 2,088		$ 2,113	$ 2,152	$ 2,207
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		99,332			81,030
Gross Balance, Liabilities		53,059			52,587
Fair Value, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		1,092			2,301
Gross Balance, Liabilities		1,565			1,550
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		52			95
Fair Value, Nonrecurring [Member] | Residential mortgages [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[1]	6
Fair Value, Nonrecurring [Member] | Impaired commercial loans [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[2]	30			37
Fair Value, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		30			37
Fair Value, Nonrecurring [Member] | Level 3 [Member] | Residential mortgages [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[1]	0
Fair Value, Nonrecurring [Member] | Level 3 [Member] | Impaired commercial loans [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[2]	30			37
Derivative financial assets [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[3]	31,190			30,330
Derivative financial assets [Member] | Fair Value, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[3]	276			179
Trading assets, excluding derivatives [Member] | Level 3 [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		16	[4]	16	16	[4]
Trading assets, excluding derivatives [Member] | Level 3 [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		90		95	92
Trading assets, excluding derivatives [Member] | Fair Value, Recurring [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		16			16
Trading assets, excluding derivatives [Member] | Fair Value, Recurring [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		90			92
Trading assets, excluding derivatives [Member] | Fair Value, Recurring [Member] | Level 3 [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		16			16
Trading assets, excluding derivatives [Member] | Fair Value, Recurring [Member] | Level 3 [Member] | Student loan asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure		90			92
Other assets [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	[5]	1		$ 1	4		$ 12	$ 15	$ 15
Other assets [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[6]	1			4
Other assets [Member] | Fair Value, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	[6]	$ 1			$ 4
Measurement Input, Loss Severity Rates [Member] | Fair Value, Nonrecurring [Member] | Level 3 [Member] | Impaired commercial loans [Member] | Minimum [Member] | Third Party Appraisal [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Loans Held-for-sale, Measurement Input		0			0.13
Measurement Input, Loss Severity Rates [Member] | Fair Value, Nonrecurring [Member] | Level 3 [Member] | Impaired commercial loans [Member] | Maximum [Member] | Third Party Appraisal [Member]
Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items]
Loans Held-for-sale, Measurement Input		0.65			1
[1]	At June 30, 2019, the fair value of the loans held for sale was below cost.
[2]	Certain commercial loans have undergone troubled debt restructurings and are considered impaired. As a matter of practical expedient, we measure the credit impairment of a collateral-dependent loan based on the fair value of the collateral asset. The collateral often involves real estate properties that are illiquid due to market conditions. As a result, these loans are classified as a Level 3 fair value measurement within the fair value hierarchy.
[3]	Includes trading derivative assets of $3,045 million and $3,048 million and trading derivative liabilities of $3,086 million and $2,690 million at June 30, 2019 and December 31, 2018, respectively, as well as derivatives held for hedging and commitments accounted for as derivatives. See Note 9, "Derivative Financial Instruments," for additional information. Excluding changes in fair value of a derivative instrument associated with a qualifying cash flow hedge, which are recognized initially in other comprehensive income (loss), derivative assets and liabilities are recorded at fair value through net income
[4]	Gains (losses) on trading assets, excluding derivatives are included in trading revenue in the consolidated statement of income.
[5]	Represents contingent consideration receivable associated with the sale of a portion of our PB business. Gains (losses) associated with this transaction are included in other income (loss) in the consolidated statement of income.
[6]	Represents contingent consideration receivable associated with the sale of a portion of our PB business.

Fair Value Measurements - Add_2

Fair Value Measurements - Additional Information Relating To Asset-Backed Securities and Collateralized Debt Obligations (Detail) $ in Millions	Jun. 30, 2019USD ($)
AAA - A Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	$ 144	[1]
Student loans [Member] | AAA - A Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	90	[1]
Collateralized debt obligations [Member] | AAA - A Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	54	[1]
Collateralized debt obligations [Member] | BBB -B Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	32	[1]
Other [Member] | AAA - A Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	53	[1]
Other [Member] | AAA - A Rating [Member] | Level 2 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	0	[1]
Other [Member] | BBB -B Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	60	[1]
Other [Member] | BBB -B Rating [Member] | Level 2 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	0	[1]
Trading assets, excluding derivatives [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	192	[1]
Available-for-sale securities [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	113
Available-for-sale securities [Member] | Level 2 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	36
Available-for-sale securities [Member] | AAA - A Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	53	[1]
Available-for-sale securities [Member] | AAA - A Rating [Member] | Level 2 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	36	[1]
Estimate of fair value [Member] | AAA - A Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	144	[1]
Estimate of fair value [Member] | Student loans [Member] | AAA - A Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	90	[1]
Estimate of fair value [Member] | Collateralized debt obligations [Member] | AAA - A Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	54	[1]
Estimate of fair value [Member] | Collateralized debt obligations [Member] | BBB -B Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	32	[1]
Estimate of fair value [Member] | Other [Member] | AAA - A Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	53	[1]
Estimate of fair value [Member] | Other [Member] | BBB -B Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	60	[1]
Estimate of fair value [Member] | Trading assets, excluding derivatives [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	192	[1]
Estimate of fair value [Member] | Available-for-sale securities [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	149
Estimate of fair value [Member] | Available-for-sale securities [Member] | AAA - A Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	89	[1]
Alt [Member] | Home Equity [Member] | AAA - A Rating [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	0	[1]
Alt [Member] | Home Equity [Member] | AAA - A Rating [Member] | Level 2 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	36	[1]
Alt [Member] | Estimate of fair value [Member] | Home Equity [Member] | AAA - A Rating [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	36	[1]
Subprime [Member] | Residential mortgage - Subprime [Member] | CCC - Unrated [Member] | Level 3 [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	16	[1]
Subprime [Member] | Estimate of fair value [Member] | Residential mortgage - Subprime [Member] | CCC - Unrated [Member]
Fair Value Of Other Financial Instrument [Line Items]
Trading asset-backed securities and related collateral	$ 16	[1]
[1]	We utilize Standard and Poor's ("S&P") as the primary source of credit ratings in the tables above. If S&P ratings are not available, ratings by Moody's and Fitch are used in that order. Ratings for CDOs represent the ratings associated with the underlying collateral.

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Value and Estimated Fair Value of Financial Instruments (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Federal funds sold and securities purchased under agreements to resell	$ 5,289	$ 10,168
Securities held-to-maturity	13,927	14,670
Loans, net of allowance for credit losses	71,865	68,437	$ 65,868
Loans held for sale	191	512
Deposits	116,961	110,955	$ 114,355
Deposits held for sale	0	10
Long-term debt	30,849	30,628
Commercial Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	151	394
Consumer Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	40	118
Consumer Loans [Member] | Residential Mortgage [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	40	65
Consumer Loans [Member] | Other consumer [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	0	53
Level 1 [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Short-term financial assets	1,196	1,514
Federal funds sold and securities purchased under agreements to resell	0	0
Securities held-to-maturity	0	0
Short-term financial liabilities	0	0
Deposits held for sale		0
Long-term debt	0	0
Level 1 [Member] | Commercial Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	0	0
Loans held for sale	0	0
Level 1 [Member] | Consumer Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	0	0
Level 1 [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	0	0
Level 1 [Member] | Consumer Loans [Member] | Other consumer [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale		0
Level 1 [Member] | Deposits Without Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	0	0
Level 1 [Member] | Deposits With Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	0	0
Level 2 [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Short-term financial assets	11,736	15,700
Federal funds sold and securities purchased under agreements to resell	5,289	10,168
Securities held-to-maturity	14,011	14,443
Short-term financial liabilities	8,444	3,626
Deposits held for sale		10
Long-term debt	19,185	19,688
Level 2 [Member] | Commercial Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	0	0
Loans held for sale	23	285
Level 2 [Member] | Consumer Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	0	0
Level 2 [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	40	65
Level 2 [Member] | Consumer Loans [Member] | Other consumer [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale		0
Level 2 [Member] | Deposits Without Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	91,305	91,794
Level 2 [Member] | Deposits With Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	17,096	10,933
Level 3 [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Short-term financial assets	31	23
Federal funds sold and securities purchased under agreements to resell	0	0
Securities held-to-maturity	0	0
Short-term financial liabilities	31	23
Deposits held for sale		0
Long-term debt	0	0
Level 3 [Member] | Commercial Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	54,350	50,671
Loans held for sale	0	0
Level 3 [Member] | Consumer Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	19,260	18,878
Level 3 [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	1	0
Level 3 [Member] | Consumer Loans [Member] | Other consumer [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale		53
Level 3 [Member] | Deposits Without Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	0	0
Level 3 [Member] | Deposits With Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	0	0
Carrying Value [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Short-term financial assets	12,963	17,237
Federal funds sold and securities purchased under agreements to resell	5,289	10,168
Securities held-to-maturity	13,927	14,670
Short-term financial liabilities	8,458	3,643
Deposits held for sale		10
Long-term debt	18,870	19,379
Carrying Value [Member] | Commercial Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	52,226	48,884
Loans held for sale	23	285
Carrying Value [Member] | Consumer Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	19,639	19,553
Carrying Value [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	40	65
Carrying Value [Member] | Consumer Loans [Member] | Other consumer [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale		53
Carrying Value [Member] | Deposits Without Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	91,305	91,794
Carrying Value [Member] | Deposits With Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	17,201	10,996
Estimate of fair value [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Short-term financial assets	12,963	17,237
Federal funds sold and securities purchased under agreements to resell	5,289	10,168
Securities held-to-maturity	14,011	14,443
Short-term financial liabilities	8,475	3,649
Deposits held for sale		10
Long-term debt	19,185	19,688
Estimate of fair value [Member] | Commercial Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	54,350	50,671
Loans held for sale	23	285
Estimate of fair value [Member] | Consumer Loans [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans, net of allowance for credit losses	19,260	18,878
Estimate of fair value [Member] | Consumer Loans [Member] | Residential Mortgage [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale	41	65
Estimate of fair value [Member] | Consumer Loans [Member] | Other consumer [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Loans held for sale		53
Estimate of fair value [Member] | Deposits Without Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	91,305	91,794
Estimate of fair value [Member] | Deposits With Fixed Maturities [Member]
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Deposits	$ 17,096	$ 10,933

Litigation and Regulatory Mat_2

Litigation and Regulatory Matters - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Expense related to various legal matters	$ 3,000,000	$ 16,000,000	$ 3,000,000	$ 510,000,000
Estimate of reasonably possible loss	$ 375,000,000		$ 375,000,000

New Accounting Pronouncements (

New Accounting Pronouncements (Details) - USD ($) $ in Millions		Jan. 01, 2019	Jun. 30, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liabilities			$ 786
Operating lease ROU assets	[1]		$ 735
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liabilities		$ 780
Operating lease ROU assets		780
Increase in retained earnings, after tax		$ 27
[1]	Reported net of level lease adjustments and exit cost obligations.