M&T Bank (MTB) 10-Q 2 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 26, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	MTB
Entity Registrant Name	M&T BANK CORP
Entity Central Index Key	0000036270
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		136,622,163

Consolidated Balance Sheet (Una

Consolidated Balance Sheet (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Assets
Cash and due from banks	$ 1,267,260	$ 1,605,439
Interest-bearing deposits at banks	7,602,897	8,105,197
Trading account	276,322	185,584
Investment securities (includes pledged securities that can be sold or repledged of $471,572 at March 31, 2019; $487,365 at December 31, 2018)
Available for sale (cost: $8,398,686 at March 31, 2019; $8,869,423 at December 31, 2018)	8,325,584	8,682,509
Held to maturity (fair value: $3,699,596 at March 31, 2019; $3,255,483 at December 31, 2018)	3,714,699	3,316,640
Equity and other securities (cost: $468,232 at March 31, 2019; $677,187 at December 31, 2018)	496,557	693,664
Total investment securities	12,536,840	12,692,813
Loans and leases	88,897,260	88,733,492
Unearned discount	(257,377)	(267,015)
Loans and leases, net of unearned discount	88,639,883	88,466,477
Allowance for credit losses	(1,019,337)	(1,019,444)
Loans and leases, net	87,620,546	87,447,033
Premises and equipment	1,044,761	647,408
Goodwill	4,593,112	4,593,112
Core deposit and other intangible assets	43,947	47,067
Accrued interest and other assets	5,039,520	4,773,750
Total assets	120,025,205	120,097,403
Liabilities
Noninterest-bearing deposits	29,966,753	32,256,668
Savings and interest-checking deposits	52,932,297	50,963,744
Time deposits	6,501,509	6,124,254
Deposits at Cayman Islands office	1,069,191	811,906
Total deposits	90,469,750	90,156,572
Short-term borrowings	3,602,566	4,398,378
Accrued interest and other liabilities	1,889,336	1,637,348
Long-term borrowings	8,476,024	8,444,914
Total liabilities	104,437,676	104,637,212
Shareholders' equity
Preferred stock, $1.00 par, 1,000,000 shares authorized; Issued and outstanding: Liquidation preference of $1,000 per share: 731,500 shares at March 31, 2019 and December 31, 2018; Liquidation preference of $10,000 per share: 50,000 shares at March 31, 2019 and December 31, 2018	1,231,500	1,231,500
Common stock, $.50 par, 250,000,000 shares authorized, 159,741,898 shares issued at March 31, 2019; 159,765,044 shares issued at December 31, 2018	79,871	79,883
Common stock issuable, 21,324 shares at March 31, 2019; 24,563 shares at December 31, 2018	1,514	1,726
Additional paid-in capital	6,568,480	6,579,342
Retained earnings	11,842,371	11,516,672
Accumulated other comprehensive income (loss), net	(288,009)	(420,081)
Treasury stock — common, at cost — 23,126,505 shares at March 31, 2019; 21,255,275 shares at December 31, 2018	(3,848,198)	(3,528,851)
Total shareholders’ equity	15,587,529	15,460,191
Total liabilities and shareholders’ equity	$ 120,025,205	$ 120,097,403

Consolidated Balance Sheet (U_2

Consolidated Balance Sheet (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Pledged securities that can be sold or repledged	$ 471,572	$ 487,365
Investment securities, available for sale, amortized cost	8,398,686	8,869,423
Investment securities, held to maturity, fair value	3,699,596	3,255,483
Equity and other securities, cost	$ 468,232	$ 677,187
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	1,000,000	1,000,000
Common stock, par value	$ 0.50	$ 0.50
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	159,741,898	159,765,044
Common stock issuable, shares	21,324	24,563
Treasury stock, common shares	23,126,505	21,255,275
Series A Series C Series And E Preferred Stock [Member]
Preferred stock, shares issued	731,500	731,500
Preferred stock, shares outstanding	731,500	731,500
Preferred stock, liquidation preference per share	$ 1,000	$ 1,000
Series F Preferred Stock [Member]
Preferred stock, shares issued	50,000	50,000
Preferred stock, shares outstanding	50,000	50,000
Preferred stock, liquidation preference per share	$ 10,000	$ 10,000

Consolidated Statement of Incom

Consolidated Statement of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Interest income
Loans and leases, including fees	$ 1,117,913	$ 979,969
Investment securities
Fully taxable	80,411	82,852
Exempt from federal taxes	95	248
Deposits at banks	27,407	18,677
Other	483	404
Total interest income	1,226,309	1,082,150
Interest expense
Savings and interest-checking deposits	76,138	40,527
Time deposits	21,081	10,936
Deposits at Cayman Islands office	4,738	381
Short-term borrowings	6,713	883
Long-term borrowings	67,579	53,906
Total interest expense	176,249	106,633
Net interest income	1,050,060	975,517
Provision for credit losses	22,000	43,000
Net interest income after provision for credit losses	1,028,060	932,517
Other income
Brokerage services income	12,476	13,392
Trading account and foreign exchange gains	10,802	4,637
Gain (loss) on bank investment securities	11,841	(9,431)
Other revenues from operations	134,437	126,302
Total other income	500,765	458,696
Other expense
Salaries and employee benefits	499,200	463,428
Equipment and net occupancy	79,347	74,797
Outside data processing and software	52,417	48,429
FDIC assessments	9,426	20,280
Advertising and marketing	20,275	16,248
Printing, postage and supplies	9,855	9,319
Amortization of core deposit and other intangible assets	5,020	6,632
Other costs of operations	218,808	294,211
Total other expense	894,348	933,344
Income before taxes	634,477	457,869
Income taxes	151,735	105,259
Net income	482,742	352,610
Net income available to common shareholders
Basic	462,086	332,748
Diluted	$ 462,086	$ 332,749
Net income per common share
Basic	$ 3.35	$ 2.24
Diluted	$ 3.35	$ 2.23
Average common shares outstanding
Basic	137,889	148,688
Diluted	137,920	148,905
Mortgage Banking Revenues [Member]
Other income
Revenue from contract with customer	$ 95,311	$ 87,306
Service Charges on Deposit Accounts [Member]
Other income
Revenue from contract with customer	103,112	105,115
Trust Income [Member]
Other income
Revenue from contract with customer	$ 132,786	$ 131,375

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Partners Capital [Abstract]
Net income	$ 482,742	$ 352,610
Other comprehensive income (loss), net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	84,591	(100,684)
Cash flow hedges adjustments	44,921	(10,442)
Foreign currency translation adjustment	275	1,290
Defined benefit plans liability adjustments	2,285	7,260
Total other comprehensive income (loss)	132,072	(102,576)
Total comprehensive income	$ 614,814	$ 250,034

Consolidated Statement of Cash

Consolidated Statement of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net income	$ 482,742	$ 352,610
Adjustments to reconcile net income to net cash provided by operating activities
Provision for credit losses	22,000	43,000
Depreciation and amortization of premises and equipment	50,982	27,281
Amortization of capitalized servicing rights	16,170	11,656
Amortization of core deposit and other intangible assets	5,020	6,632
Provision for deferred income taxes	13,441	(124,772)
Asset write-downs	1,919	3,192
Net gain on sales of assets	(5,171)	(4,547)
Net change in accrued interest receivable, payable	(35,071)	(14,803)
Net change in other accrued income and expense	(171,304)	165,114
Net change in loans originated for sale	202,670	(72,403)
Net change in trading account assets and liabilities	(170,092)	91,219
Net cash provided by operating activities	413,306	484,179
Cash flows from investing activities
Proceeds from sales of investment securities Available for sale		100
Proceeds from sales of investment securities equity and other	312,743	254,860
Proceeds from maturities of investment securities Available for sale	371,714	349,294
Proceeds from maturities of investment securities Held to maturity	99,960	123,923
Purchases of investment securities Available for sale	(1,595)	(100)
Purchases of investment securities Held to maturity	(495,277)
Purchases of investment securities equity and other	(103,795)	(288,259)
Net (increase) decrease in loans and leases	(412,670)	303,886
Net (increase) decrease in interest-bearing deposits at banks	502,300	(1,056,531)
Capital expenditures, net	(30,710)	(9,544)
Net decrease in loan servicing advances	22,891	115,163
Other, net	5,700	(41,322)
Net cash provided (used) by investing activities	271,261	(248,530)
Cash flows from financing activities
Net increase (decrease) in deposits	313,849	(1,484,629)
Net increase (decrease) in short-term borrowings	(795,812)	1,451,030
Proceeds from long-term borrowings		999,594
Payments on long-term borrowings	(1,139)	(504,192)
Purchases of treasury stock	(365,628)	(720,966)
Dividends paid — common	(139,595)	(112,318)
Dividends paid — preferred	(17,368)	(17,368)
Other, net	(17,053)	24,976
Net cash used by financing activities	(1,022,746)	(363,873)
Net decrease in cash, cash equivalents and restricted cash	(338,179)	(128,224)
Cash, cash equivalents and restricted cash at beginning of period	1,605,439	1,420,888
Cash, cash equivalents and restricted cash at end of period	1,267,260	1,292,664
Supplemental disclosure of cash flow information
Interest received during the period	1,194,023	1,077,676
Interest paid during the period	191,309	118,342
Income taxes paid during the period	149,548	37,999
Supplemental schedule of noncash investing and financing activities
Real estate acquired in settlement of loans	24,840	15,410
Securitization of residential mortgage loans allocated to Available-for-sale investment securities	5,379	5,128
Securitization of residential mortgage loans allocated to capitalized servicing rights	83	$ 64
Adoption of operating lease standard - Right-of-use assets	393,877
Adoption of operating lease standard - Other liabilities	398,810
Additions to right-of-use assets under operating leases	$ 20,410

Consolidated Statement of Chang

Consolidated Statement of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands		Total	Preferred Stock [Member]	Common Stock [Member]	Common Stock Issuable [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Series A Warrants [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), Net [Member]	Treasury Stock [Member]	Treasury Stock [Member]Series A Warrants [Member]
Beginning balance at Dec. 31, 2017		$ 16,250,819	$ 1,231,500	$ 79,909	$ 1,847	$ 6,590,855		$ 10,164,804	$ (363,814)	$ (1,454,282)
Cumulative effect of change in accounting principle — equity securities		(16,853)						16,853	(16,853)
Total comprehensive income		250,034						352,610	(102,576)
Preferred stock cash dividends	[1]	(18,130)						(18,130)
Exercise of stock warrants into common stock							$ (3,455)				$ 3,455
Purchases of treasury stock		(720,966)								(720,966)
Stock-based compensation plans:
Compensation expense, net		5,833		(25)		(15,362)				21,220
Exercises of stock options, net		42,100				(1,945)				44,045
Stock purchase plan		11,124				2,358				8,766
Directors’ stock plan		589				74				515
Deferred compensation plans, net, including dividend equivalents		(48)			(172)	(244)		(18)		386
Common stock cash dividends		(111,661)						(111,661)
Ending balance at Mar. 31, 2018		15,709,694	1,231,500	79,884	1,675	6,572,281		10,404,458	(483,243)	(2,096,861)
Beginning balance at Dec. 31, 2018		15,460,191	1,231,500	79,883	1,726	6,579,342		11,516,672	(420,081)	(3,528,851)
Total comprehensive income		614,814						482,742	132,072
Preferred stock cash dividends	[1]	(18,130)						(18,130)
Purchases of treasury stock		(365,628)								(365,628)
Stock-based compensation plans:
Compensation expense, net		18,120		(12)		(7,606)				25,738
Exercises of stock options, net		4,727				(2,818)				7,545
Stock purchase plan		11,832				(67)				11,899
Directors’ stock plan		529				(84)				613
Deferred compensation plans, net, including dividend equivalents		(64)			(212)	(316)		(22)		486
Performance share unit dividends						29		(29)
Common stock cash dividends		(138,862)						(138,862)
Ending balance at Mar. 31, 2019		$ 15,587,529	$ 1,231,500	$ 79,871	$ 1,514	$ 6,568,480		$ 11,842,371	$ (288,009)	$ (3,848,198)
[1]	For each of the three-month periods ended March 31, 2019 and 2018, dividends per preferred share were: Preferred Series A- $15.9375; Preferred Series C - $15.9375; Preferred Series E - $16.125; and Preferred Series F - $128.125. See accompanying notes to financial statements.

Consolidated Statement of Cha_2

Consolidated Statement of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Preferred Series A [Member]
Preferred stock per share dividend amount	$ 15.9375	$ 15.9375
Preferred Series C [Member]
Preferred stock per share dividend amount	15.9375	15.9375
Preferred Series E [Member]
Preferred stock per share dividend amount	16.125	16.125
Series F Preferred Stock [Member]
Preferred stock per share dividend amount	128.125	128.125
Retained Earnings [Member]
Common stock per share dividend amount	$ 1	$ 0.75
Series A Warrants [Member] | Treasury Stock [Member]
Exercise of warrants into shares of common stock		36,974
Exercise of warrants into shares of common stock		22,553

Significant accounting policies

Significant accounting policies	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Significant accounting policies	1. Significant accounting policies The consolidated interim financial statements of M&T Bank Corporation (“M&T”) and subsidiaries (“the Company”) were compiled in accordance with generally accepted accounting principles (“GAAP”) using the accounting policies set forth in note 1 of Notes to Financial Statements included in Form 10-K for the year ended December 31, 2018 (“2018 Annual Report”), except that effective January 1, 2019 the Company adopted accounting guidance that is discussed in notes 3, 4 and 16 herein. The financial statements contain all adjustments which are, in the opinion of management, necessary for a fair statement of the Company’s financial position, results of operations and cash flows for the interim periods presented.

Investment securities

Investment securities	3 Months Ended
	Mar. 31, 2019
Investments Debt And Equity Securities [Abstract]
Investment securities	2. Investment securities On January 1, 2018, the Company adopted amended guidance requiring equity investments with readily determinable fair values to be measured at fair value with changes in fair value recognized in the consolidated statement of income. This amended guidance excludes equity method investments, investments in consolidated subsidiaries, exchange membership ownership interests, and Federal Home Loan Bank of New York and Federal Reserve Bank of New York capital stock. Upon adoption the Company reclassified $17 million, after-tax effect, from accumulated other comprehensive income to retained earnings, representing the difference between fair value and the cost basis of equity investments with readily determinable fair values at January 1, 2018. The amortized cost and estimated fair value of investment securities were as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (In thousands) March 31, 2019 Investment securities available for sale: U.S. Treasury and federal agencies $ 1,144,288 $ 4 $ 4,864 $ 1,139,428 Obligations of states and political subdivisions 1,181 4 4 1,181 Mortgage-backed securities: Government issued or guaranteed 7,115,459 29,959 91,511 7,053,907 Privately issued 16 — — 16 Other debt securities 137,742 1,249 7,939 131,052 8,398,686 31,216 104,318 8,325,584 Investment securities held to maturity: U.S. Treasury and federal agencies 944,230 735 15 944,950 Obligations of states and political subdivisions 6,810 27 — 6,837 Mortgage-backed securities: Government issued or guaranteed 2,652,219 11,876 19,472 2,644,623 Privately issued 107,858 12,806 21,060 99,604 Other debt securities 3,582 — — 3,582 3,714,699 25,444 40,547 3,699,596 Total debt securities $ 12,113,385 $ 56,660 $ 144,865 $ 12,025,180 Equity and other securities: Readily marketable equity — at fair value $ 48,261 $ 28,913 $ 588 $ 76,586 Other — at cost 419,971 — — 419,971 Total equity and other securities $ 468,232 $ 28,913 $ 588 $ 496,557 2. Investment securities, continued Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (In thousands) December 31, 2018 Investment securities available for sale: U.S. Treasury and federal agencies $ 1,346,782 $ — $ 9,851 $ 1,336,931 Obligations of states and political subdivisions 1,660 4 5 1,659 Mortgage-backed securities: Government issued or guaranteed 7,383,340 15,754 182,103 7,216,991 Privately issued 24 — 2 22 Other debt securities 137,617 770 11,481 126,906 8,869,423 16,528 203,442 8,682,509 Investment securities held to maturity: U.S. Treasury and federal agencies 446,542 — 239 446,303 Obligations of states and political subdivisions 7,494 22 12 7,504 Mortgage-backed securities: Government issued or guaranteed 2,745,776 4,165 55,111 2,694,830 Privately issued 113,160 12,345 22,327 103,178 Other debt securities 3,668 — — 3,668 3,316,640 16,532 77,689 3,255,483 Total debt securities $ 12,186,063 $ 33,060 $ 281,131 $ 11,937,992 Equity and other securities: Readily marketable equity — at fair value $ 77,440 $ 17,295 $ 818 $ 93,917 Other — at cost 599,747 — — 599,747 Total equity and other securities $ 677,187 $ 17,295 $ 818 $ 693,664 There were no significant gross realized gains or losses from sales of investment securities for the quarters ended March 31, 2019 and 2018. Net unrealized gains recorded as gain (loss) on bank investment securities in the consolidated statement of income during the three months ended March 31, 2019 were $12 million, compared with losses of $9 million during the three months ended March 31, 2018. At March 31, 2019, the amortized cost and estimated fair value of debt securities by contractual maturity were as follows: Amortized Cost Estimated Fair Value (In thousands) Debt securities available for sale: Due in one year or less $ 1,141,640 1,136,864 Due after one year through five years 9,470 9,355 Due after five years through ten years 102,101 99,642 Due after ten years 30,000 25,800 1,283,211 1,271,661 Mortgage-backed securities available for sale 7,115,475 7,053,923 $ 8,398,686 8,325,584 Debt securities held to maturity: Due in one year or less $ 947,176 947,905 Due after one year through five years 3,864 3,882 Due after ten years 3,582 3,582 954,622 955,369 Mortgage-backed securities held to maturity 2,760,077 2,744,227 $ 3,714,699 3,699,596 2. Investment securities, continued A summary of investment securities that as of March 31, 2019 and December 31, 2018 had been in a continuous unrealized loss position for less than twelve months and those that had been in a continuous unrealized loss position for twelve months or longer follows: Less Than 12 Months 12 Months or More Fair Value Unrealized Losses Fair Value Unrealized Losses (In thousands) March 31, 2019 Investment securities available for sale: U.S. Treasury and federal agencies $ 274 (1 ) 1,137,550 (4,863 ) Obligations of states and political subdivisions — — 507 (4 ) Mortgage-backed securities: Government issued or guaranteed 18,447 (111 ) 5,076,762 (91,400 ) Other debt securities 36,500 (294 ) 67,662 (7,645 ) 55,221 (406 ) 6,282,481 (103,912 ) Investment securities held to maturity: U.S. Treasury and federal agencies 249,082 (15 ) — — Mortgage-backed securities: Government issued or guaranteed — — 1,620,580 (19,472 ) Privately issued — — 51,091 (21,060 ) 249,082 (15 ) 1,671,671 (40,532 ) Total $ 304,303 (421 ) 7,954,152 (144,444 ) December 31, 2018 Investment securities available for sale: U.S. Treasury and federal agencies $ 273 (2 ) 1,335,559 (9,849 ) Obligations of states and political subdivisions 629 (5 ) — — Mortgage-backed securities: Government issued or guaranteed 405,558 (2,892 ) 5,646,773 (179,211 ) Privately issued 22 (2 ) — — Other debt securities 53,478 (2,187 ) 66,014 (9,294 ) 459,960 (5,088 ) 7,048,346 (198,354 ) Investment securities held to maturity: U.S. Treasury and federal agencies 446,303 (239 ) — — Obligations of states and political subdivisions — — 3,126 (12 ) Mortgage-backed securities: Government issued or guaranteed 179,354 (989 ) 2,082,723 (54,122 ) Privately issued — — 51,943 (22,327 ) 625,657 (1,228 ) 2,137,792 (76,461 ) Total $ 1,085,617 (6,316 ) 9,186,138 (274,815 ) The Company owned 1,166 individual debt securities with aggregate gross unrealized losses of $145 million at March 31, 2019. Based on a review of each of the securities in the investment securities portfolio at March 31, 2019, the Company concluded that it expected to recover the amortized cost basis of its investment. As of March 31, 2019, the Company does not intend to sell nor is it anticipated that it would be required to sell any of its impaired investment securities at a loss. At March 31, 2019, the Company has not identified events or changes in circumstances which may have a significant adverse effect on the fair value of the $420 million of cost method equity securities.

Loans and leases and the allowa

Loans and leases and the allowance for credit losses	3 Months Ended
	Mar. 31, 2019
Receivables [Abstract]
Loans and leases and the allowance for credit losses	3. Loans and leases and the allowance for credit losses A summary of current, past due and nonaccrual loans as of March 31, 2019 and December 31, 2018 follows: Current 30-89 Days Past Due Accruing Loans Due 90 Days or More (a) Accruing Loans Acquired a Discount Past Due 90 days or More (b) Purchased Impaired (c) Nonaccrual Total (In thousands) March 31, 2019 Commercial, financial, leasing, etc. $ 22,701,500 141,555 1,047 283 — 245,819 $ 23,090,204 Real estate: Commercial 25,441,419 159,209 7,394 158 10,305 207,709 25,826,194 Residential builder and developer 1,738,846 2,190 — — 549 4,392 1,745,977 Other commercial construction 7,036,036 31,152 31,032 — 640 19,899 7,118,759 Residential 13,337,558 406,106 199,940 6,425 187,631 210,266 14,347,926 Residential — limited documentation 2,186,132 71,354 — — 79,658 84,863 2,422,007 Consumer: Home equity lines and loans 4,634,634 31,145 — 4,871 — 69,245 4,739,895 Recreational finance 4,295,732 22,549 — 235 — 10,972 4,329,488 Automobile 3,619,015 62,846 — — — 21,209 3,703,070 Other 1,257,839 14,420 4,844 32,023 — 7,237 1,316,363 Total $ 86,248,711 942,526 244,257 43,995 278,783 881,611 $ 88,639,883 December 31, 2018 Commercial, financial, leasing, etc. $ 22,701,020 39,798 2,567 168 — 234,423 $ 22,977,976 Real estate: Commercial 25,250,983 134,474 11,457 10 9,769 203,672 25,610,365 Residential builder and developer 1,665,178 20,333 — — — 4,798 1,690,309 Other commercial construction 6,982,077 43,615 14,344 — 641 22,205 7,062,882 Residential 13,591,790 404,808 189,682 6,650 203,044 233,352 14,629,326 Residential — limited documentation 2,278,040 72,544 — — 89,851 84,685 2,525,120 Consumer: Home equity lines and loans 4,758,513 25,416 — 5,033 — 71,292 4,860,254 Recreational finance 4,085,781 29,947 — 235 — 11,199 4,127,162 Automobile 3,555,757 79,804 — — — 23,359 3,658,920 Other 1,271,811 15,598 4,477 27,654 — 4,623 1,324,163 Total $ 86,140,950 866,337 222,527 39,750 303,305 893,608 $ 88,466,477 (a) Excludes loans acquired at a discount. (b) Loans acquired at a discount that were recorded at fair value at acquisition date. This category does not include purchased impaired loans that are presented separately. (c) Accruing loans acquired at a discount that were impaired at acquisition date and recorded at fair value. 3. Loans and leases and the allowance for credit losses, continued One-to-four family residential mortgage loans held for sale were $178 million and $205 million at March 31, 2019 and December 31, 2018, respectively. Commercial real estate loans held for sale were $166 million at March 31, 2019 and $347 million at December 31, 2018. The outstanding principal balance and the carrying amount of loans acquired at a discount that were recorded at fair value at the acquisition date and included in the consolidated balance sheet were as follows: March 31, December 31, 2019 2018 (In thousands) Outstanding principal balance $ 960,990 $ 1,016,785 Carrying amount: Commercial, financial, leasing, etc. 25,060 27,073 Commercial real estate 125,310 135,047 Residential real estate 442,260 473,511 Consumer 93,486 91,860 $ 686,116 $ 727,491 Purchased impaired loans included in the table above totaled $279 million at March 31, 2019 and $303 million at December 31, 2018, representing less than 1% of the Company’s assets as of each date. A summary of changes in the accretable yield for loans acquired at a discount for the three months ended March 31, 2019 and 2018 follows: Three Months Ended March 31 2019 2018 Purchased Other Purchased Other Impaired Acquired Impaired Acquired (In thousands) Balance at beginning of period $ 147,210 $ 96,907 $ 157,918 $ 133,162 Interest income (18,082 ) (9,717 ) (9,819 ) (15,112 ) Reclassifications from nonaccretable balance 11,189 4,865 908 207 Other (a) — 1,632 — (73 ) Balance at end of period $ 140,317 $ 93,687 $ 149,007 $ 118,184 (a) Other changes in expected cash flows including changes in interest rates and prepayment assumptions. Changes in the allowance for credit losses for the three months ended March 31, 2019 were as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Unallocated Total (In thousands) Beginning balance $ 330,055 341,655 69,125 200,564 78,045 $ 1,019,444 Provision for credit losses 6,271 (4,203 ) (2,447 ) 22,883 (504 ) 22,000 Net charge-offs Charge-offs (8,500 ) (283 ) (3,372 ) (32,945 ) — (45,100 ) Recoveries 7,794 826 1,830 12,543 — 22,993 Net (charge-offs) recoveries (706 ) 543 (1,542 ) (20,402 ) — (22,107 ) Ending balance $ 335,620 337,995 65,136 203,045 77,541 $ 1,019,337 3. Loans and leases and the allowance for credit losses, continued Changes in the allowance for credit losses for the three months ended March 31, 2018 were as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Unallocated Total (In thousands) Beginning balance $ 328,599 374,085 65,405 170,809 78,300 $ 1,017,198 Provision for credit losses 7,230 (5,225 ) 10,486 29,814 695 43,000 Net charge-offs Charge-offs (14,581 ) (1,366 ) (4,354 ) (36,451 ) — (56,752 ) Recoveries 4,823 223 1,510 9,669 — 16,225 Net (charge-offs) recoveries (9,758 ) (1,143 ) (2,844 ) (26,782 ) — (40,527 ) Ending balance $ 326,071 367,717 73,047 173,841 78,995 $ 1,019,671 Despite the allocation in the preceding tables, the allowance for credit losses is general in nature and is available to absorb losses from any loan or lease type. In establishing the allowance for credit losses, the Company estimates losses attributable to specific troubled credits identified through both normal and targeted credit review processes and also estimates losses inherent in other loans and leases on a collective basis. For purposes of determining the level of the allowance for credit losses, the Company evaluates its loan and lease portfolio by loan type. The amounts of loss components in the Company’s loan and lease portfolios are determined through a loan-by-loan analysis of larger balance commercial loans and commercial real estate loans that are in nonaccrual status and by applying loss factors to groups of loan balances based on loan type and management’s classification of such loans under the Company’s loan grading system. Measurement of the specific loss components is typically based on expected future cash flows, collateral values and other factors that may impact the borrower’s ability to pay. In determining the allowance for credit losses, the Company utilizes a loan grading system which is applied to commercial and commercial real estate credits on an individual loan basis. Loan grades are assigned loss component factors that reflect the Company’s loss estimate for each group of loans and leases. Factors considered in assigning loan grades and loss component factors include borrower-specific information related to expected future cash flows and operating results, collateral values, geographic location, financial condition and performance, payment status, and other information; levels of and trends in portfolio charge-offs and recoveries; levels of and trends in portfolio delinquencies and impaired loans; changes in the risk profile of specific portfolios; trends in volume and terms of loans; effects of changes in credit concentrations; and observed trends and practices in the banking industry. 3. Loans and leases and the allowance for credit losses, continued I nformation with respect to loans and leases that were considered impaired as of March 31, 2019 and December 31, 2018 and for the three-month periods ended March 31, 2019 and 2018 follows. March 31, 2019 December 31, 2018 Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance (In thousands) With an allowance recorded: Commercial, financial, leasing, etc. $ 201,337 220,116 50,192 153,478 175,549 46,034 Real estate: Commercial 102,247 119,062 10,449 110,253 125,117 11,937 Residential builder and developer 6,805 7,399 327 5,981 6,557 462 Other commercial construction 10,696 13,624 703 10,563 11,113 640 Residential 121,351 142,872 5,291 124,974 147,817 5,402 Residential — limited documentation 71,113 86,276 3,000 74,156 90,066 3,000 Consumer: Home equity lines and loans 47,363 52,583 9,025 47,982 53,248 9,135 Recreational finance 5,539 5,740 1,147 6,138 9,163 1,261 Automobile 3,522 3,603 729 3,527 3,599 729 Other 5,612 11,902 1,128 5,203 8,380 1,046 575,585 663,177 81,991 542,255 630,609 79,646 With no related allowance recorded: Commercial, financial, leasing, etc. 91,355 97,342 — 105,507 136,128 — Real estate: Commercial 125,289 138,095 — 113,376 124,657 — Residential builder and developer 2,756 2,781 — 2,593 2,602 — Other commercial construction 9,203 9,432 — 11,710 11,880 — Residential 19,535 25,771 — 15,379 20,496 — Residential — limited documentation 6,145 10,434 — 5,631 9,796 — 254,283 283,855 — 254,196 305,559 — Total: Commercial, financial, leasing, etc. 292,692 317,458 50,192 258,985 311,677 46,034 Real estate: Commercial 227,536 257,157 10,449 223,629 249,774 11,937 Residential builder and developer 9,561 10,180 327 8,574 9,159 462 Other commercial construction 19,899 23,056 703 22,273 22,993 640 Residential 140,886 168,643 5,291 140,353 168,313 5,402 Residential — limited documentation 77,258 96,710 3,000 79,787 99,862 3,000 Consumer: Home equity lines and loans 47,363 52,583 9,025 47,982 53,248 9,135 Recreational finance 5,539 5,740 1,147 6,138 9,163 1,261 Automobile 3,522 3,603 729 3,527 3,599 729 Other 5,612 11,902 1,128 5,203 8,380 1,046 Total $ 829,868 947,032 81,991 796,451 936,168 79,646 3. Loans and leases and the allowance for credit losses, continued Three Months Ended March 31, 2019 Three Months Ended March 31, 2018 Interest Income Recognized Interest Income Recognized Average Recorded Investment Total Cash Basis Average Recorded Investment Total Cash Basis (In thousands) Commercial, financial, leasing, etc. $ 265,248 3,038 3,038 272,172 783 783 Real estate: Commercial 225,374 1,091 1,091 181,846 3,147 3,147 Residential builder and developer 8,875 115 115 9,840 1,682 1,682 Other commercial construction 20,398 564 564 10,102 6 6 Residential 140,403 2,022 666 121,209 1,902 902 Residential — limited documentation 78,238 1,353 208 85,595 1,728 696 Consumer: Home equity lines and loans 47,556 416 62 48,797 414 86 Recreational finance 6,023 142 4 1,458 63 2 Automobile 3,530 54 19 13,125 224 15 Other 5,218 122 4 1,661 22 1 Total $ 800,863 8,917 5,771 745,805 9,971 7,320 Commercial loans and commercial real estate loans with a lower expectation of default are assigned one of ten possible “pass” loan grades and are generally ascribed lower loss factors when determining the allowance for credit losses. Loans with an elevated level of credit risk are classified as “criticized” and are ascribed a higher loss factor when determining the allowance for credit losses. Criticized loans may be classified as “nonaccrual” if the Company no longer expects to collect all amounts according to the contractual terms of the loan agreement or the loan is delinquent 90 days or more. Furthermore, criticized nonaccrual commercial loans and commercial real estate loans are considered impaired and, as a result, specific loss allowances on such loans are established within the allowance for credit losses to the extent appropriate in each individual instance. The following table summarizes the loan grades applied to the various classes of the Company’s commercial loans and commercial real estate loans. Real Estate Commercial, Residential Other Financial, Builder and Commercial Leasing, etc. Commercial Developer Construction (In thousands) March 31, 2019 Pass $ 21,734,455 24,686,100 1,535,068 6,870,882 Criticized accrual 1,109,930 932,385 206,517 227,978 Criticized nonaccrual 245,819 207,709 4,392 19,899 Total $ 23,090,204 25,826,194 1,745,977 7,118,759 December 31, 2018 Pass $ 21,693,705 24,539,706 1,546,002 6,890,562 Criticized accrual 1,049,848 866,987 139,509 150,115 Criticized nonaccrual 234,423 203,672 4,798 22,205 Total $ 22,977,976 25,610,365 1,690,309 7,062,882 3. Loans and leases and the allowance for credit losses, continued In determining the allowance for credit losses, residential real estate loans and consumer loans are generally evaluated collectively after considering such factors as payment performance and recent loss experience and trends, which are mainly driven by current collateral values in the market place as well as the amount of loan defaults. Loss rates on such loans are determined by reference to recent charge-off history and are evaluated (and adjusted if deemed appropriate) through consideration of other factors including near-term forecasted loss estimates developed by the Company’s credit department. In arriving at such forecasts, the Company considers the current estimated fair value of its collateral based on geographical adjustments for home price depreciation/appreciation and overall borrower repayment performance. With regard to collateral values, the realizability of such values by the Company contemplates repayment of any first lien position prior to recovering amounts on a second lien position. However, residential real estate loans and outstanding balances of home equity loans and lines of credit that are more than 150 days past due are generally evaluated for collectibility on a loan-by-loan basis giving consideration to estimated collateral values. The carrying value of residential real estate loans and home equity loans and lines of credit for which a partial charge-off has been recognized totaled $29 million and $22 million, respectively, at March 31, 2019 and $29 million and $23 million, respectively, at December 31, 2018. Residential real estate loans and home equity loans and lines of credit that were more than 150 days past due but did not require a partial charge-off because the net realizable value of the collateral exceeded the outstanding customer balance were $19 million and $33 million, respectively, at March 31, 2019 and $21 million and $31 million, respectively, at December 31, 2018. The Company also measures additional losses for purchased impaired loans when it is probable that the Company will be unable to collect all cash flows expected at acquisition plus additional cash flows expected to be collected arising from changes in estimates after acquisition. The determination of the allocated portion of the allowance for credit losses is very subjective. Given that inherent subjectivity and potential imprecision involved in determining the allocated portion of the allowance for credit losses, the Company also provides an inherent unallocated portion of the allowance. The unallocated portion of the allowance is intended to recognize probable losses that are not otherwise identifiable and includes management’s subjective determination of amounts necessary to provide for the possible use of imprecise estimates in determining the allocated portion of the allowance. Therefore, the level of the unallocated portion of the allowance is primarily reflective of the inherent imprecision in the various calculations used in determining the allocated portion of the allowance for credit losses. Other factors that could also lead to changes in the unallocated portion include the effects of expansion into new markets for which the Company does not have the same degree of familiarity and experience regarding portfolio performance in changing market conditions, the introduction of new loan and lease product types, and other risks associated with the Company’s loan portfolio that may not be specifically identifiable. 3. Loans and leases and the allowance for credit losses, continued The allocation of the allowance for credit losses summarized on the basis of the Company’s impairment methodology was as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Total (In thousands) March 31, 2019 Individually evaluated for impairment $ 50,192 11,479 8,291 12,029 $ 81,991 Collectively evaluated for impairment 285,428 326,516 47,028 191,016 849,988 Purchased impaired — — 9,817 — 9,817 Allocated $ 335,620 337,995 65,136 203,045 941,796 Unallocated 77,541 Total $ 1,019,337 December 31, 2018 Individually evaluated for impairment $ 46,034 13,039 8,402 12,171 $ 79,646 Collectively evaluated for impairment 284,021 328,616 48,326 188,393 849,356 Purchased impaired — — 12,397 — 12,397 Allocated $ 330,055 341,655 69,125 200,564 941,399 Unallocated 78,045 Total $ 1,019,444 The recorded investment in loans and leases summarized on the basis of the Company’s impairment methodology was as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Total (In thousands) March 31, 2019 Individually evaluated for impairment $ 292,692 256,996 218,144 62,036 $ 829,868 Collectively evaluated for impairment 22,797,512 34,422,440 16,284,500 14,026,780 87,531,232 Purchased impaired — 11,494 267,289 — 278,783 Total $ 23,090,204 34,690,930 16,769,933 14,088,816 $ 88,639,883 December 31, 2018 Individually evaluated for impairment $ 258,985 254,476 220,140 62,850 $ 796,451 Collectively evaluated for impairment 22,718,991 34,098,670 16,641,411 13,907,649 87,366,721 Purchased impaired — 10,410 292,895 — 303,305 Total $ 22,977,976 34,363,556 17,154,446 13,970,499 $ 88,466,477 During the normal course of business, the Company modifies loans to maximize recovery efforts. If the borrower is experiencing financial difficulty and a concession is granted, the Company considers such modifications as troubled debt restructurings and classifies those loans as either nonaccrual loans or renegotiated loans. The types of concessions that the Company grants typically include principal deferrals and interest rate concessions, but may also include other types of concessions. 3. Loans and leases and the allowance for credit losses, continued The table that follows summarizes the Company’s loan modification activities that were considered troubled debt restructurings for the three-month periods ended March 31, 2019 and 2018: Post-modification (a) Number Pre- modification Recorded Investment Principal Deferral Interest Rate Reduction Combination of Concession Types Total Three Months Ended March 31, 2019 (Dollars in thousands) Commercial, financial, leasing, etc. 65 $ 30,615 $ 6,474 $ — $ 24,270 $ 30,744 Real estate: Commercial 15 9,241 987 — 7,967 8,954 Residential builder and developer 2 1,330 1,068 — — 1,068 Other commercial construction 1 418 — — 366 366 Residential 17 3,816 1,751 — 2,273 4,024 Residential — limited documentation 1 236 239 — — 239 Consumer: Home equity lines and loans 7 476 37 — 454 491 Recreational finance 4 88 88 — — 88 Automobile 20 317 280 — 37 317 Total 132 $ 46,537 $ 10,924 $ — $ 35,367 $ 46,291 Three Months Ended March 31, 2018 Commercial, financial, leasing, etc. 56 $ 47,994 $ 35,673 $ 624 $ 13,047 $ 49,344 Real estate: Commercial 20 6,780 5,824 — 927 6,751 Other commercial construction 1 752 746 — — 746 Residential 47 12,636 6,945 — 6,902 13,847 Residential — limited documentation 2 295 267 — 118 385 Consumer: Home equity lines and loans 14 1,348 4 — 1,348 1,352 Recreational finance 2 49 49 — — 49 Automobile 8 148 148 — — 148 Total 150 $ 70,002 $ 49,656 $ 624 $ 22,342 $ 72,622 (a) Financial effects impacting the recorded investment included principal payments or advances, charge-offs and capitalized escrow arrearages. The present value of interest rate concessions, discounted at the effective rate of the original loan, was not material. Troubled debt restructurings are considered to be impaired loans and for purposes of establishing the allowance for credit losses are evaluated for impairment giving consideration to the impact of the modified loan terms on the present value of the loan’s expected cash flows. Impairment of troubled debt restructurings that have subsequently defaulted may also be measured based on the loan’s observable market price or the fair value of collateral if the loan is collateral-dependent. Charge-offs may also be recognized on troubled debt restructurings that have subsequently defaulted. Loans that were modified as troubled debt restructurings during the twelve months ended March 31, 2019 and 2018 and for which there was a subsequent payment default during the three-month periods ended March 31, 2019 and 2018, respectively, were not material. The amount of foreclosed residential real estate property held by the Company was $81 million and $77 million at March 31, 2019 and December 31, 2018, respectively. There were $382 million and $391 million at March 31, 2019 and December 31, 2018, respectively, in loans secured by residential real estate that were in the process of foreclosure. Of all loans in the process of foreclosure at March 31, 2019, approximately 38% were classified as purchased impaired and 21% were government guaranteed. 3. Loans and leases and the allowance for credit losses, continued The Company’s loan and lease portfolio includes commercial lease financing receivables consisting of direct financing and leveraged leases for machinery and equipment, railroad equipment, commercial trucks and trailers, and aircraft. Certain leases contain payment schedules that are tied to variable interest rate indices. In general, early termination options are provided if the lessee is not in default, returns the leased equipment and pays an early termination fee. Additionally, options to purchase the underlying asset by the lessee are generally at the fair market value of the equipment. Effective January 1, 2019, the Company adopted new guidance related to lease accounting published by the Financial Accounting Standards Board (“FASB”). Under the new guidance, the accounting applied by lessors is largely unchanged from previous GAAP, however, the guidance eliminates the accounting model for leveraged leases that commence after the effective date of the guidance. A summary of lease financing receivables follows: March 31, December 31, 2019 2018 (In thousands) Commercial leases: Direct financings: Lease payments receivable $ 1,140,794 $ 1,155,464 Estimated residual value of leased assets 82,686 85,169 Unearned income (106,797 ) (110,458 ) Investment in direct financings 1,116,683 1,130,175 Leveraged leases: Lease payments receivable 82,841 85,007 Estimated residual value of leased assets 81,261 81,261 Unearned income (33,273 ) (33,717 ) Investment in leveraged leases 130,829 132,551 Total investment in leases $ 1,247,512 $ 1,262,726 Deferred taxes payable arising from leveraged leases $ 73,808 $ 74,995 Included within the estimated residual value of leased assets at March 31, 2019 and December 31, 2018 were $35 million and $39 million, respectively, in residual value associated with direct financing leases that are guaranteed by the lessees or others. At March 31, 2019, the minimum future lease payments to be received from lease financings were as follows: (In thousands) Twelve-month period ending March 31: 2020 $ 322,403 2021 302,912 2022 220,516 2023 148,313 2024 84,610 Later years 144,881 $ 1,223,635

Operating Leases

Operating Leases	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Operating leases	4. Operating leases The January 1, 2019 adoption of new lease accounting guidance resulted in the Company recording right-of-use assets and lease liabilities in the consolidated balance sheet for all operating leases with a term greater than twelve months. In addition, the Company elected the practical expedients that (1) reassessment is not needed for whether any existing contracts are or contain leases, (2) reassessment of the classification of existing operating and finance leases is not required, and (3) a lease that has a term of twelve months or less is not required to apply the asset and liability recognition requirements. The Company determines whether a contract contains a lease based on whether a contract, or a part of a contract, conveys the right to control the use of an identified asset for a period of time in exchange for consideration. If it is determined that a contract contains a lease, the consideration in the contract is separated between lease and nonlease components (for example, taxes or common area maintenance). In calculating the present value of the lease payments, the Company has utilized its incremental borrowing rate based on electing the original lease term to account for each lease component. The right-of-use assets and lease liabilities relate to banking offices and other space occupied by the Company and use of certain equipment under noncancelable operating lease agreements, which prior to the adoption of the guidance were not reflected in the consolidated balance sheet. As of March 31, 2019, the Company reported right-of-use assets recognized as a component of “premises and equipment” and lease liabilities recognized as a component of “accrued interest and other liabilities” in the consolidated balance sheet, as follows: March 31, 2019 (In thousands) Right-of-use assets $ 392,847 Lease liabilities 419,958 The Company’s noncancelable operating lease agreements expire at various dates over the next 23 years. Real estate leases generally consist of fixed monthly rental payments with certain leases containing escalation clauses. Any variable lease payments or payments for nonlease components are recognized in the consolidated statement of income as a component of “equipment and net occupancy” expense based on actual costs incurred. Some of these real estate leases contain lessee options to extend the term. Those options are included in the lease term when it is determined that it is reasonably certain the option will be exercised. The Company has noncancelable operating lease agreements for certain equipment related to ATMs, servers, printers and mail machines that are used in the normal course of operations. The ATM leases are either based on the rights to a specific square footage or a license agreement whereby the Company has the right to operate an ATM in a landlord's location. The lease terms generally contain both fixed payments and variable payments that are transaction-based. Given the transaction-based nature of the variable payments, they are excluded from the measurement of the right-of-use asset and lease liability and are recognized in the consolidated statement of income as a component of “equipment and net occupancy” expense when incurred. 4. Operating leases, continued The following table presents information about the Company’s lease costs for operating leases recorded in the consolidated balance sheet, cash paid toward lease liabilities, and the weighted-average remaining term and discount rates of the operating leases. Three Months Ended March 31, 2019 (Dollars in thousands) Lease cost Operating lease cost $ 24,639 Short-term lease cost 34 Variable lease cost 466 Sublease income (1,917 ) Total net lease cost $ 23,222 Other information Right-of-use assets obtained in exchange for new operating lease liabilities $ 20,410 Cash paid toward lease liabilities 25,656 Weighted-average remaining lease term 7 years Weighted-average discount rate 3.2 % Minimum lease payments under noncancelable operating leases are summarized in the following table. These minimum lease payments are not materially different from those reported in the 2018 Annual Report. (In thousands) Twelve-month period ending March 31: 2020 $ 93,460 2021 87,025 2022 71,369 2023 58,847 2024 41,034 Later years 111,683 Total lease payments $ 463,418 Less: imputed interest 43,460 Total $ 419,958 All other operating leasing activities were not material to the Company’s consolidated results of operations.

Borrowings

Borrowings	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Borrowings	5. Borrowings M&T had $523 million of fixed and variable rate junior subordinated deferrable interest debentures ("Junior Subordinated Debentures") outstanding at March 31, 2019 that are held by various trusts that were issued in connection with the issuance by those trusts of preferred capital securities ("Capital Securities") and common securities ("Common Securities"). The proceeds from the issuances of the Capital Securities and the Common Securities were used by the trusts to purchase the Junior Subordinated Debentures. The Common Securities of each of those trusts are wholly owned by M&T and are the only class of each trust's securities possessing general voting powers. The Capital Securities represent preferred undivided interests in the assets of the corresponding trust. Under the Federal Reserve Board’s risk-based capital guidelines, the securities are includable in M&T’s Tier 2 regulatory capital. Holders of the Capital Securities receive preferential cumulative cash distributions unless M&T exercises its right to extend the payment of interest on the Junior Subordinated Debentures as allowed by the terms of each such debenture, in which case payment of distributions on the respective Capital Securities will be deferred for comparable periods. During an extended interest period, M&T may not pay dividends or distributions on, or repurchase, redeem or acquire any shares of its capital stock. In general, the agreements governing the Capital Securities, in the aggregate, provide a full, irrevocable and unconditional guarantee by M&T of the payment of distributions on, the redemption of, and any liquidation distribution with respect to the Capital Securities. The obligations under such guarantee and the Capital Securities are subordinate and junior in right of payment to all senior indebtedness of M&T. The Capital Securities will remain outstanding until the Junior Subordinated Debentures are repaid at maturity, are redeemed prior to maturity or are distributed in liquidation to the trusts. The Capital Securities are mandatorily redeemable in whole, but not in part, upon repayment at the stated maturity dates (ranging from 2027 to 2033) of the Junior Subordinated Debentures or the earlier redemption of the Junior Subordinated Debentures in whole upon the occurrence of one or more events set forth in the indentures relating to the Capital Securities, and in whole or in part at any time after an optional redemption prior to contractual maturity contemporaneously with the optional redemption of the related Junior Subordinated Debentures in whole or in part, subject to possible regulatory approval. Also included in long-term borrowings are agreements to repurchase securities of $406 million and $409 million at March 31, 2019 and December 31, 2018, respectively. The agreements reflect various repurchase dates through 2020, however, the contractual maturities of the underlying investment securities extend beyond such repurchase dates. The agreements are subject to legally enforceable master netting arrangements, however, the Company has not offset any amounts related to these agreements in its consolidated financial statements. The Company posted collateral consisting primarily of government guaranteed mortgage-backed securities of $425 million and $428 million at March 31, 2019 and December 31, 2018, respectively .

Revenue from contracts with cus

Revenue from contracts with customers	3 Months Ended
	Mar. 31, 2019
Revenue From Contract With Customer [Abstract]
Revenue from contracts with customers	6. Revenue from contracts with customers A significant amount of the Company’s revenues are derived from net interest income on financial assets and liabilities, mortgage banking revenues, trading account and foreign exchange gains, investment securities gains, loan and letter of credit fees, income from bank-owned life insurance, and certain other revenues that are generally excluded from the scope of accounting guidance for revenue from contracts with customers. For noninterest income revenue streams, the Company recognizes the expected amount of consideration as revenue when the performance obligations related to the services under the terms of a contract are satisfied. The Company’s contracts generally do not contain terms that necessitate significant judgment to determine the amount of revenue to recognize. The Company generally charges customer accounts or otherwise bills customers upon completion of its services. Typically the Company’s contracts with customers have a duration of one year or less and payment for services is received at least annually, but oftentimes more frequently as services are provided. At March 31, 2019 and December 31, 2018, the Company had $54 million and $56 million, respectively, of uncollected amounts receivable related to recognized revenue from the sources in the accompanying tables. Such amounts are classified in accrued interest and other assets in the Company’s consolidated balance sheet. In certain situations the Company is paid in advance of providing services and defers the recognition of revenue until its service obligation is satisfied. At each of March 31, 2019 and December 31, 2018, the Company had deferred revenue of $43 million related to the sources in the accompanying tables recorded in accrued interest and other liabilities in the consolidated balance sheet. The following tables summarize sources of the Company’s noninterest income during the three-month periods ended March 31, 2019 and 2018 that are subject to the noted accounting guidance. Business Banking Commercial Banking Commercial Real Estate Discretionary Portfolio Residential Mortgage Banking Retail Banking All Other Total Three Months Ended March 31, 2019 (In thousands) Classification in consolidated statement of income Service charges on deposit accounts $ 15,109 23,210 2,526 — 2 61,151 1,114 $ 103,112 Trust income 5 214 — — — — 132,567 132,786 Brokerage services income — — — — — — 12,476 12,476 Other revenues from operations: Merchant discount and credit card fees 8,882 12,092 606 — — 3,138 420 25,138 Other — 1,002 1,788 401 1,064 8,494 10,488 23,237 $ 23,996 36,518 4,920 401 1,066 72,783 157,065 $ 296,749 Three Months Ended March 31, 2018 Classification in consolidated statement of income Service charges on deposit accounts $ 15,404 24,654 2,764 — 3 60,601 1,689 $ 105,115 Trust income — — — — — — 131,375 131,375 Brokerage services income — — — — — — 13,392 13,392 Other revenues from operations: Merchant discount and credit card fees 7,503 12,712 554 — — 3,388 615 24,772 Other — 1,563 859 452 1,043 9,865 9,108 22,890 $ 22,907 38,929 4,177 452 1,046 73,854 156,179 $ 297,544

Pension plans and other postret

Pension plans and other postretirement benefits	3 Months Ended
	Mar. 31, 2019
Compensation And Retirement Disclosure [Abstract]
Pension plans and other postretirement benefits	7. Pension plans and other postretirement benefits The Company provides defined benefit pension and other postretirement benefits (including health care and life insurance benefits) to qualified retired employees. Net periodic defined benefit cost for defined benefit plans consisted of the following: Pension Benefits Other Postretirement Benefits Three Months Ended March 31 2019 2018 2019 2018 (In thousands) Service cost $ 4,087 5,103 200 226 Interest cost on projected benefit obligation 20,200 18,805 603 557 Expected return on plan assets (30,600 ) (30,875 ) — — Amortization of prior service cost (credit) 125 125 (1,175 ) (1,175 ) Amortization of net actuarial loss (gain) 4,450 11,100 (300 ) (200 ) Net periodic cost (benefit) $ (1,738 ) 4,258 (672 ) (592 ) Service cost is reflected in salaries and employee benefits expense in the consolidated statement of income. The other components of net periodic benefit cost are reflected in other costs of operations. Expenses incurred in connection with the Company's defined contribution pension and retirement savings plans totaled $22.2 million and $21.3 million for the three months ended March 31, 2019 and 2018, respectively, and are included in salaries and employee benefits expense.

Earnings per common share

Earnings per common share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Earnings per common share	8. Earnings per common share The computations of basic earnings per common share follow: Three Months Ended March 31 2019 2018 (In thousands, except per share) Income available to common shareholders: Net income $ 482,742 352,610 Less: Preferred stock dividends (a) (18,130 ) (18,130 ) Net income available to common equity 464,612 334,480 Less: Income attributable to unvested stock-based compensation awards (2,526 ) (1,732 ) Net income available to common shareholders $ 462,086 332,748 Weighted-average shares outstanding: Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards 138,637 149,470 Less: Unvested stock-based compensation awards (748 ) (782 ) Weighted-average shares outstanding 137,889 148,688 Basic earnings per common share $ 3.35 2.24 (a) Including impact of not as yet declared cumulative dividends. 8. Earnings per common share, continued The computations of diluted earnings per common share follow: Three Months Ended March 31 2019 2018 (In thousands, except per share) Net income available to common equity $ 464,612 334,480 Less: Income attributable to unvested stock-based compensation awards (2,526 ) (1,731 ) Net income available to common shareholders $ 462,086 332,749 Adjusted weighted-average shares outstanding: Common and unvested stock-based compensation awards 138,637 149,470 Less: Unvested stock-based compensation awards (748 ) (782 ) Plus: Incremental shares from assumed conversion of stock-based compensation awards and warrants to purchase common stock 31 217 Adjusted weighted-average shares outstanding 137,920 148,905 Diluted earnings per common share $ 3.35 2.23 GAAP defines unvested share-based awards that contain nonforfeitable rights to dividends or dividend equivalents (whether paid or unpaid) as participating securities that shall be included in the computation of earnings per common share pursuant to the two-class method. The Company has issued stock-based compensation awards in the form of restricted stock and restricted stock units which, in accordance with GAAP, are considered participating securities. Stock-based compensation awards and warrants to purchase common stock of M&T representing 280,818 and 237,584 common shares during the three-month periods ended March 31, 2019 and 2018, respectively, were not included in the computations of diluted earnings per common share because the effect on those periods would have been antidilutive.

Comprehensive income

Comprehensive income	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Comprehensive income	9. Comprehensive income The following tables display the components of other comprehensive income (loss) and amounts reclassified from accumulated other comprehensive income (loss) to net income: Investment Defined Benefit Total Amount Income Securities Plans Other Before Tax Tax Net (In thousands) Balance — January 1, 2019 $ (200,107 ) (354,502 ) (14,719 ) $ (569,328 ) 149,247 $ (420,081 ) Other comprehensive income before reclassifications: Unrealized holding gains, net 113,805 — — 113,805 (29,902 ) 83,903 Foreign currency translation adjustment — — 348 348 (73 ) 275 Unrealized gains on cash flow hedges — — 54,347 54,347 (14,288 ) 40,059 Total other comprehensive income before reclassifications 113,805 — 54,695 168,500 (44,263 ) 124,237 Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: Amortization of unrealized holding losses on held-to-maturity (“HTM”) securities 928 — — 928 (a) (245 ) 683 Losses realized in net income 7 — — 7 (b) (2 ) 5 Accretion of net gain on terminated cash flow hedges — — (28 ) (28 ) (c) 7 (21 ) Net yield adjustment from cash flow hedges currently in effect — — 6,625 6,625 (a) (1,742 ) 4,883 Amortization of prior service credit — (1,050 ) — (1,050 ) (d) 276 (774 ) Amortization of actuarial losses — 4,150 — 4,150 (d) (1,091 ) 3,059 Total other comprehensive income 114,740 3,100 61,292 179,132 (47,060 ) 132,072 Balance — March 31, 2019 $ (85,367 ) (351,402 ) 46,573 $ (390,196 ) 102,187 $ (288,009 ) Balance — January 1, 2018 $ (59,957 ) (413,168 ) (20,165 ) $ (493,290 ) 129,476 $ (363,814 ) Cumulative effect of change in accounting principle — equity securities (22,795 ) — — (22,795 ) 5,942 (16,853 ) Other comprehensive income before reclassifications: Unrealized holding losses, net (145,457 ) — — (145,457 ) 44,176 (101,281 ) Foreign currency translation adjustment — — 1,632 1,632 (342 ) 1,290 Unrealized losses on cash flow hedges — — (14,719 ) (14,719 ) 3,870 (10,849 ) Total other comprehensive income (loss) before reclassifications (145,457 ) — (13,087 ) (158,544 ) 47,704 (110,840 ) Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: Amortization of unrealized holding losses on HTM securities 810 — — 810 (a) (213 ) 597 Accretion of net gain on terminated cash flow hedges — — (28 ) (28 ) (c) 7 (21 ) Net yield adjustment from cash flow hedges currently in effect — — 580 580 (a) (152 ) 428 Amortization of prior service credit — (1,050 ) — (1,050 ) (d) 276 (774 ) Amortization of actuarial losses — 10,900 — 10,900 (d) (2,866 ) 8,034 Total other comprehensive income (loss) (144,647 ) 9,850 (12,535 ) (147,332 ) 44,756 (102,576 ) Balance — March 31, 2018 $ (227,399 ) (403,318 ) (32,700 ) $ (663,417 ) 180,174 $ (483,243 ) (a) Included in interest income. (b) Included in gain (loss) on bank investment securities. (c) Included in interest expense. (d) Included in other costs of operations. Accumulated other comprehensive income (loss), net consisted of the following: Investment Defined Benefit Securities Plans Other Total (In thousands) Balance — December 31, 2018 $ (147,526 ) (261,303 ) (11,252 ) $ (420,081 ) Net gain during period 84,591 2,285 45,196 132,072 Balance — March 31, 2019 $ (62,935 ) (259,018 ) 33,944 $ (288,009 )

Derivative financial instrument

Derivative financial instruments	3 Months Ended
	Mar. 31, 2019
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative financial instruments	10. Derivative financial instruments As part of managing interest rate risk, the Company enters into interest rate swap agreements to modify the repricing characteristics of certain portions of the Company’s portfolios of earning assets and interest-bearing liabilities. The Company designates interest rate swap agreements utilized in the management of interest rate risk as either fair value hedges or cash flow hedges. Interest rate swap agreements are generally entered into with counterparties that meet established credit standards and most contain master netting, collateral and/or settlement provisions protecting the at-risk party. Based on adherence to the Company’s credit standards and the presence of the netting, collateral or settlement provisions, the Company believes that the credit risk inherent in these contracts was not material as of March 31, 2019. The net effect of interest rate swap agreements was to decrease net interest income by $13 million during the three months ended March 31, 2019 and increase net interest income by $1 million during the three months ended March 31, 2018. Information about interest rate swap agreements entered into for interest rate risk management purposes summarized by type of financial instrument the swap agreements were intended to hedge follows: Weighted- Average Rate Notional Average Estimated Fair Value Amount Maturity Fixed Variable Gain (Loss) (a) (In thousands) (In years) (In March 31, 2019 Fair value hedges: Fixed rate long-term borrowings (b) $ 4,450,000 2.6 2.47 % 3.04 % $ (4,390 ) Cash flow hedges: Interest payments on variable rate commercial real estate loans (b)(c) 29,750,000 1.4 2.29 % 2.49 % (12,534 ) Total $ 34,200,000 1.6 $ (16,924 ) December 31, 2018 Fair value hedges: Fixed rate long-term borrowings (b) $ 4,450,000 2.8 2.47 % 3.02 % $ 4,219 Cash flow hedges: Interest payments on variable rate commercial real estate loans (b)(d) 15,400,000 1.3 1.52 % 2.35 % 1,311 Total $ 19,850,000 1.7 $ 5,530 (a) Certain clearinghouse exchanges consider payments by counterparties for variation margin on derivative instruments to be settlements of those positions. The impact of such treatment at March 31, 2019 and December 31, 2018 was a reduction of the estimated fair value losses on interest rate swap agreements designated as fair value hedges of $11.9 million and $54.7 million, respectively, and on interest rate swap agreements designated as cash flow hedges of $65.7 million and $9.1 million, respectively. (b) Under the terms of these agreements, the Company receives settlement amounts at a fixed rate and pays at a variable rate. (c) (d) . The Company utilizes commitments to sell residential and commercial real estate loans to hedge the exposure to changes in the fair value of real estate loans held for sale. Such commitments have generally been designated as fair value hedges. The Company also utilizes commitments to sell real estate loans to offset the exposure to changes in fair value of certain commitments to originate real estate loans for sale. Derivative financial instruments used for trading account purposes included interest rate contracts, foreign exchange and other option contracts, foreign exchange forward and spot contracts, and financial futures. Interest rate contracts entered into for trading account purposes had notional values of $43.3 billion and $42.9 billion at March 31, 2019 and December 31, 2018, respectively. The notional amounts of foreign currency and other option and futures contracts entered into for trading account purposes aggregated $832 million and $763 million at March 31, 2019 and December 31, 2018, respectively. 10. Derivative financial instruments, continued Information about the fair values of derivative instruments in the Company’s consolidated balance sheet and consolidated statement of income follows: Asset Derivatives Liability Derivatives Fair Value Fair Value March 31, December 31, March 31, December 31, 2019 2018 2019 2018 (In thousands) Derivatives designated and qualifying as hedging instruments Interest rate swap agreements (a) $ 267 $ 5,530 $ 17,191 $ — Commitments to sell real estate loans (a) 1,145 1,090 3,413 6,434 1,412 6,620 20,604 6,434 Derivatives not designated and qualifying as hedging instruments Mortgage-related commitments to originate real estate loans for sale (a) 8,059 9,304 626 1,592 Commitments to sell real estate loans (a) 3,687 3,702 2,843 4,535 Trading: Interest rate contracts (b) 199,404 118,687 92,383 169,255 Foreign exchange and other option and futures contracts (b) 7,880 10,549 6,390 8,870 219,030 142,242 102,242 184,252 Total derivatives $ 220,442 $ 148,862 $ 122,846 $ 190,686 (a) Asset derivatives are reported in other assets and liability derivatives are reported in other liabilities. (b) Asset derivatives are reported in trading account assets and liability derivatives are reported in other liabilities. The impact of variation margin payments at March 31, 2019 and December 31, 2018 was a reduction of the estimated fair value of interest rate contracts in the trading account in an asset position of $88.1 million and $170.7 million, respectively, and in a liability position of $122.8 million and $49.7 million, respectively. Amount of Gain (Loss) Recognized Three Months Ended March 31, 2019 Three Months Ended March 31, 2018 Derivative Hedged Item Derivative Hedged Item (In thousands) Derivatives in fair value hedging relationships Interest rate swap agreements: Fixed rate long-term borrowings (a) $ 34,180 (34,014 ) $ (42,390 ) 42,370 Derivatives not designated as hedging instruments Trading: Interest rate contracts (b) $ 2,711 $ (1,605 ) Foreign exchange and other option and futures contracts (b) 1,613 2,631 Total $ 4,324 $ 1,026 (a) Reported as an adjustment to interest expense. (b) Reported as trading account and foreign exchange gains. Carrying Amount of the Hedged Item Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount of the Hedged Item March 31, 2019 December 31, 2018 March 31, 2019 December 31, 2018 (In thousands) Location in the Consolidated Balance Sheet of the Hedged Items in Fair Value Hedges Long-term debt $ 4,428,645 $ 4,394,109 $ (17,088 ) $ (51,102 ) 10. Derivative financial instruments, continued The amount of gain (loss) recognized in the consolidated statement of income associated with derivatives designated as cash flow hedges was not material. The Company also has commitments to sell and commitments to originate residential and commercial real estate loans that are considered derivatives. The Company designates certain of the commitments to sell real estate loans as fair value hedges of real estate loans held for sale. The Company also utilizes commitments to sell real estate loans to offset the exposure to changes in the fair value of certain commitments to originate real estate loans for sale. As a result of these activities, net unrealized pre-tax gains related to hedged loans held for sale, commitments to originate loans for sale and commitments to sell loans were approximately $16 million and $18 million at March 31, 2019 and December 31, 2018, respectively. Changes in unrealized gains and losses are included in mortgage banking revenues and, in general, are realized in subsequent periods as the related loans are sold and commitments satisfied. The Company does not offset derivative asset and liability positions in its consolidated financial statements. The Company’s exposure to credit risk by entering into derivative contracts is mitigated through master netting agreements and collateral posting or settlement requirements. Master netting agreements covering interest rate and foreign exchange contracts with the same party include a right to set-off that becomes enforceable in the event of default, early termination or under other specific conditions. The aggregate fair value of derivative financial instruments in a liability position and the net liability positions with counterparties, which are subject to enforceable master netting arrangements, was $20 million and $21 million at March 31, 2019 and December 31, 2018, respectively. The Company was required to post collateral relating to those positions of $20 million and $18 million at March 31, 2019 and December 31, 2018, respectively. Certain of the Company’s derivative financial instruments contain provisions that require the Company to maintain specific credit ratings from credit rating agencies to avoid higher collateral posting requirements. If the Company’s debt rating were to fall below specified ratings, the counterparties of the derivative financial instruments could demand immediate incremental collateralization on those instruments in a net liability position. The aggregate fair value of all derivative financial instruments with such credit risk-related contingent features in a net liability position on March 31, 2019 was not significant. If the credit risk-related contingent features had been triggered on March 31, 2019, the Company would not have been required to post any additional collateral to counterparties. The aggregate fair value of derivative financial instruments in an asset position and the net asset positions with counterparties, which are subject to enforceable master netting arrangements, was $7 million and $18 million at March 31, 2019 and December 31, 2018, respectively. Counterparties posted collateral relating to those positions of $3 million and $16 million at March 31, 2019 and December 31, 2018, respectively. Trading account interest rate swap agreements entered into with customers are subject to the Company’s credit risk standards and often contain collateral provisions. In addition to the derivative contracts noted above, the Company clears certain derivative transactions through a clearinghouse, rather than directly with counterparties. Those transactions cleared through a clearinghouse require initial margin collateral and variation margin payments depending on the contracts being in a net asset or liability position. The amount of initial margin collateral posted by the Company was $71 million and $65 million at March 31, 2019 and December 31, 2018, respectively. The fair value asset and liability amounts of derivative contracts have been reduced by variation margin payments treated as settlements as described herein. Variation margin on derivative contracts not treated as settlements continues to represent collateral posted or received by the Company.

Variable interest entities and

Variable interest entities and asset securitizations	3 Months Ended
	Mar. 31, 2019
Text Block [Abstract]
Variable interest entities and asset securitizations	11. Variable interest entities and asset securitizations The Company’s securitization activity has consisted of securitizing loans originated for sale into government issued or guaranteed mortgage-backed securities. The amounts of those securitizations during the three-month periods ended March 31, 2019 and 2018 are presented in the Company’s consolidated statement of cash flows. The Company has not recognized any losses as a result of having securitized assets. As described in note 5, M&T has issued junior subordinated debentures payable to various trusts that have issued Capital Securities. M&T owns the common securities of those trust entities. The Company is not considered to be the primary beneficiary of those entities and, accordingly, the trusts are not included in the Company’s consolidated financial statements. At each of March 31, 2019 and December 31, 2018, the Company included the junior subordinated debentures as “long-term borrowings” in its consolidated balance sheet and recognized $23 million in other assets for its “investment” in the common securities of the trusts that will be concomitantly repaid to M&T by the respective trust from the proceeds of M&T’s repayment of the junior subordinated debentures associated with preferred capital securities described in note 5. The Company has invested as a limited partner in various partnerships that collectively had total assets of approximately $1.1 billion at March 31, 2019 and December 31, 2018. Those partnerships generally construct or acquire properties for which the investing partners are eligible to receive certain federal income tax credits in accordance with government guidelines. Such investments may also provide tax deductible losses to the partners. The partnership investments also assist the Company in achieving its community reinvestment initiatives. As a limited partner, there is no recourse to the Company by creditors of the partnerships. However, the tax credits that result from the Company’s investments in such partnerships are generally subject to recapture should a partnership fail to comply with the respective government regulations. The Company’s maximum exposure to loss of its investments in such partnerships was $517 million, including $278 million of unfunded commitments, at March 31, 2019 and $523 million, including $280 million of unfunded commitments, at December 31, 2018. Contingent commitments to provide additional capital contributions to these partnerships were not material at March 31, 2019. The Company has not provided financial or other support to the partnerships that was not contractually required. Management currently estimates that no material losses are probable as a result of the Company’s involvement with such entities. The Company, in its position as limited partner, does not direct the activities that most significantly impact the economic performance of the partnerships and, therefore, in accordance with the accounting provisions for variable interest entities, the partnership entities are not included in the Company’s consolidated financial statements. The Company’s investment in qualified affordable housing projects is amortized to income taxes in the consolidated statement of income as tax credits and other tax benefits resulting from deductible losses associated with the projects are received. The Company serves as investment advisor for certain registered money-market funds. The Company has no explicit arrangement to provide support to those funds, but may waive portions of its allowable management fees as a result of market conditions .

Fair value measurements

Fair value measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair value measurements	12. Fair value measurements GAAP permits an entity to choose to measure eligible financial instruments and other items at fair value. The Company has not made any fair value elections at March 31, 2019. Pursuant to GAAP, fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three-level hierarchy exists in GAAP for fair value measurements based upon the inputs to the valuation of an asset or liability. • Level 1 — Valuation is based on quoted prices in active markets for identical assets and liabilities. • Level 2 — Valuation is determined from quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar instruments in markets that are not active or by model-based techniques in which all significant inputs are observable in the market. • Level 3 — Valuation is derived from model-based and other techniques in which at least one significant input is unobservable and which may be based on the Company's own estimates about the assumptions that market participants would use to value the asset or liability. When available, the Company attempts to use quoted market prices in active markets to determine fair value and classifies such items as Level 1 or Level 2. If quoted market prices in active markets are not available, fair value is often determined using model-based techniques incorporating various assumptions including interest rates, prepayment speeds and credit losses. Assets and liabilities valued using model-based techniques are classified as either Level 2 or Level 3, depending on the lowest level classification of an input that is considered significant to the overall valuation. The following is a description of the valuation methodologies used for the Company's assets and liabilities that are measured on a recurring basis at estimated fair value. Trading account assets and liabilities Trading account assets and liabilities consist primarily of interest rate contracts and foreign exchange contracts with customers who require such services with offsetting positions with third parties to minimize the Company's risk with respect to such transactions. The Company generally determines the fair value of its derivative trading account assets and liabilities using externally developed pricing models based on market observable inputs and, therefore, classifies such valuations as Level 2. Mutual funds held in connection with deferred compensation and other arrangements have been classified as Level 1 valuations. Valuations of investments in municipal and other bonds can generally be obtained through reference to quoted prices in less active markets for the same or similar securities or through model-based techniques in which all significant inputs are observable and, therefore, such valuations have been classified as Level 2. Investment securities available for sale and equity securities The majority of the Company's available-for-sale investment securities have been valued by reference to prices for similar securities or through model-based techniques in which all significant inputs are observable and, therefore, such valuations have been classified as Level 2. Certain investments in mutual funds and equity securities are actively traded and, therefore, have been classified as Level 1 valuations. Real estate loans held for sale The Company utilizes commitments to sell real estate loans to hedge the exposure to changes in fair value of real estate loans held for sale. The carrying value of hedged real estate loans held for sale includes changes in estimated fair value during the hedge period. Typically, the Company attempts to hedge real estate loans held for sale from the date of close through the sale date. The fair value of hedged real estate loans held for sale is generally calculated by reference to quoted prices in secondary markets for commitments to sell real estate loans with similar characteristics and, accordingly, such loans have been classified as a Level 2 valuation. 12. Fair value measurements, continued Commitments to originate real estate loans for sale and commitments to sell real estate loans The Company enters into various commitments to originate real estate loans for sale and commitments to sell real estate loans. Such commitments are considered to be derivative financial instruments and, therefore, are carried at estimated fair value on the consolidated balance sheet. The estimated fair values of such commitments were generally calculated by reference to quoted prices in secondary markets for commitments to sell real estate loans to certain government-sponsored entities and other parties. The fair valuations of commitments to sell real estate loans generally result in a Level 2 classification. The estimated fair value of commitments to originate real estate loans for sale are adjusted to reflect the Company's anticipated commitment expirations. The estimated commitment expirations are considered significant unobservable inputs contributing to the Level 3 classification of commitments to originate real estate loans for sale. Significant unobservable inputs used in the determination of estimated fair value of commitments to originate real estate loans for sale are included in the accompanying table of significant unobservable inputs to Level 3 measurements. Interest rate swap agreements used for interest rate risk management The Company utilizes interest rate swap agreements as part of the management of interest rate risk to modify the repricing characteristics of certain portions of its portfolios of earning assets and interest-bearing liabilities. The Company generally determines the fair value of its interest rate swap agreements using externally developed pricing models based on market observable inputs and, therefore, classifies such valuations as Level 2. The Company has considered counterparty credit risk in the valuation of its interest rate swap agreement assets and has considered its own credit risk in the valuation of its interest rate swap agreement liabilities. 12. Fair value measurements, continued The following tables present assets and liabilities at March 31, 2019 and December 31, 2018 measured at estimated fair value on a recurring basis: Fair Value Measurements Level 1 (a) Level 2 (a) Level 3 (In thousands) March 31, 2019 Trading account assets $ 276,322 $ 46,521 $ 229,801 $ — Investment securities available for sale: U.S. Treasury and federal agencies 1,139,428 — 1,139,428 — Obligations of states and political subdivisions 1,181 — 1,181 — Mortgage-backed securities: Government issued or guaranteed 7,053,907 — 7,053,907 — Privately issued 16 — — 16 Other debt securities 131,052 — 131,052 — 8,325,584 — 8,325,568 16 Equity securities 76,586 43,301 33,285 — Real estate loans held for sale 344,350 — 344,350 — Other assets (b) 13,158 — 5,099 8,059 Total assets $ 9,036,000 $ 89,822 $ 8,938,103 $ 8,075 Trading account liabilities $ 98,771 $ — $ 98,771 $ — Other liabilities (b) 24,073 — 23,447 626 Total liabilities $ 122,844 $ — $ 122,218 $ 626 December 31, 2018 Trading account assets $ 185,584 $ 46,018 $ 139,566 $ — Investment securities available for sale: U.S. Treasury and federal agencies 1,336,931 — 1,336,931 — Obligations of states and political subdivisions 1,659 — 1,659 — Mortgage-backed securities: Government issued or guaranteed 7,216,991 — 7,216,991 — Privately issued 22 — — 22 Other debt securities 126,906 — 126,906 — 8,682,509 — 8,682,487 22 Equity securities 93,917 71,989 21,928 — Real estate loans held for sale 551,697 — 551,697 — Other assets (b) 19,626 — 10,322 9,304 Total assets $ 9,533,333 $ 118,007 $ 9,406,000 $ 9,326 Trading account liabilities $ 178,125 $ — $ 178,125 $ — Other liabilities (b) 12,561 — 10,969 1,592 Total liabilities $ 190,686 $ — $ 189,094 $ 1,592 (a) There were no significant transfers between Level 1 and Level 2 of the fair value hierarchy during the three months ended March 31, 2019 and the year ended December 31, 2018. (b) Comprised predominantly of interest rate swap agreements used for interest rate risk management (Level 2), commitments to sell real estate loans (Level 2) and commitments to originate real estate loans to be held for sale (Level 3). 12. Fair value measurements, continued The changes in Level 3 assets and liabilities measured at estimated fair value on a recurring basis during the three months ended March 31, 2019 and 2018 were as follows: Investment Securities Available for Sale Privately Issued Mortgage-Backed Other Assets 2019 (In thousands) Balance — January 1, 2019 $ 22 7,712 Total gains (losses) realized/unrealized: Included in earnings — 16,546 (b) Settlements (6 ) — Transfers out of Level 3 (a) — (16,825 ) (c) Balance — March 31, 2019 $ 16 7,433 Changes in unrealized gains included in earnings related to assets still held at March 31, 2019 $ — 8,525 (b) 2018 Balance — January 1, 2018 $ 28 8,303 Total gains (losses) realized/unrealized: Included in earnings — 8,130 (b) Settlements (1 ) — Transfers out of Level 3 (a) — (7,673 ) (c) Balance — March 31, 2018 $ 27 8,760 Changes in unrealized gains included in earnings related to assets still held at March 31, 2018 $ — 8,778 (b) (a) The Company’s policy for transfers between fair value levels is to recognize the transfer as of the actual date of the event or change in circumstances that caused the transfer. (b) Reported as mortgage banking revenues in the consolidated statement of income and includes the fair value of commitment issuances and expirations. (c) Transfers out of Level 3 consist of interest rate locks transferred to closed loans. The Company is required, on a nonrecurring basis, to adjust the carrying value of certain assets or provide valuation allowances related to certain assets using fair value measurements. The more significant of those assets follow. 12. Fair value measurements, continued Loans Loans are generally not recorded at fair value on a recurring basis. Periodically, the Company records nonrecurring adjustments to the carrying value of loans based on fair value measurements for partial charge-offs of the uncollectible portions of those loans. Nonrecurring adjustments also include certain impairment amounts for collateral-dependent loans when establishing the allowance for credit losses. Such amounts are generally based on the fair value of the underlying collateral supporting the loan and, as a result, the carrying value of the loan less the calculated valuation amount does not necessarily represent the fair value of the loan. Real estate collateral is typically valued using appraisals or other indications of value based on recent comparable sales of similar properties or assumptions generally observable in the marketplace and the related nonrecurring fair value measurement adjustments have been classified as Level 2, unless significant adjustments have been made to the valuation that are not readily observable by market participants. Non-real estate collateral supporting commercial loans generally consists of business assets such as receivables, inventory and equipment. Fair value estimations are typically determined by discounting recorded values of those assets to reflect estimated net realizable value considering specific borrower facts and circumstances and the experience of credit personnel in their dealings with similar borrower collateral liquidations. Such discounts were in the range of 15% to 90% at March 31, 2019. As these discounts are not readily observable and are considered significant, the valuations have been classified as Level 3. Automobile collateral is typically valued by reference to independent pricing sources based on recent sales transactions of similar vehicles, and the related nonrecurring fair value measurement adjustments have been classified as Level 2. Collateral values for other consumer installment loans are generally estimated based on historical recovery rates for similar types of loans. As these recovery rates are not readily observable by market participants, such valuation adjustments have been classified as Level 3. Loans subject to nonrecurring fair value measurement were $199 million at March 31, 2019 ($121 million and $78 million of which were classified as Level 2 and Level 3, respectively), $268 million at December 31, 2018 ($120 million and $148 million of which were classified as Level 2 and Level 3, respectively) and $178 million at March 31, 2018 ($97 million and $81 million of which were classified as Level 2 and Level 3, respectively). Changes in fair value recognized for partial charge-offs of loans and loan impairment reserves on loans held by the Company on March 31, 2019 and 2018 were decreases of $20 million and $27 million for the three-month periods ended March 31, 2019 and 2018, respectively. Assets taken in foreclosure of defaulted loans Assets taken in foreclosure of defaulted loans are primarily comprised of commercial and residential real property and are generally measured at the lower of cost or fair value less costs to sell. The fair value of the real property is generally determined using appraisals or other indications of value based on recent comparable sales of similar properties or assumptions generally observable in the marketplace, and the related nonrecurring fair value measurement adjustments have generally been classified as Level 2. Assets taken in foreclosure of defaulted loans subject to nonrecurring fair value measurement were $9 million and $19 million at March 31, 2019 and 2018, respectively. Changes in fair value recognized for those foreclosed assets held by the Company were not material during the three-month periods ended March 31, 2019 and 2018. 12. Fair value measurements, continued Significant unobservable inputs to Level 3 measurements The following tables present quantitative information about significant unobservable inputs used in the fair value measurements for certain Level 3 assets and liabilities at March 31, 2019 and December 31, 2018: Fair Value Valuation Technique Unobservable Inputs/Assumptions Range (Weighted- Average) (In March 31, 2019 Recurring fair value measurements Privately issued mortgage-backed securities $ 16 Two independent pricing quotes — — Net other assets (liabilities) (a) 7,433 Discounted cash flow Commitment expirations 0%-94% (17%) December 31, 2018 Recurring fair value measurements Privately issued mortgage-backed securities $ 22 Two independent pricing quotes — — Net other assets (liabilities) (a) 7,712 Discounted cash flow Commitment expirations 0%-95% (13%) (a) Other Level 3 assets (liabilities) consist of commitments to originate real estate loans. Sensitivity of fair value measurements to changes in unobservable inputs An increase (decrease) in the estimate of expirations for commitments to originate real estate loans would generally result in a lower (higher) fair value measurement. Estimated commitment expirations are derived considering loan type, changes in interest rates and remaining length of time until closing. 12. Fair value measurements, continued Disclosures of fair value of financial instruments The carrying amounts and estimated fair value for financial instrument assets (liabilities) are presented in the following table: March 31, 2019 Carrying Amount Estimated Fair Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 1,267,260 1,267,260 1,194,318 72,942 — Interest-bearing deposits at banks 7,602,897 7,602,897 — 7,602,897 — Trading account assets 276,322 276,322 46,521 229,801 — Investment securities 12,536,840 12,521,737 43,301 12,378,816 99,620 Loans and leases: Commercial loans and leases 23,090,204 22,755,670 — — 22,755,670 Commercial real estate loans 34,690,930 34,424,612 — 166,019 34,258,593 Residential real estate loans 16,769,933 16,764,418 — 3,877,095 12,887,323 Consumer loans 14,088,816 14,018,581 — — 14,018,581 Allowance for credit losses (1,019,337 ) — — — — Loans and leases, net 87,620,546 87,963,281 — 4,043,114 83,920,167 Accrued interest receivable 374,084 374,084 — 374,084 — Financial liabilities: Noninterest-bearing deposits $ (29,966,753 ) (29,966,753 ) — (29,966,753 ) — Savings and interest-checking deposits (52,932,297 ) (52,932,297 ) — (52,932,297 ) — Time deposits (6,501,509 ) (6,598,274 ) — (6,598,274 ) — Deposits at Cayman Islands office (1,069,191 ) (1,069,191 ) — (1,069,191 ) — Short-term borrowings (3,602,566 ) (3,602,566 ) — (3,602,566 ) — Long-term borrowings (8,476,024 ) (8,511,141 ) — (8,511,141 ) — Accrued interest payable (80,322 ) (80,322 ) — (80,322 ) — Trading account liabilities (98,771 ) (98,771 ) — (98,771 ) — Other financial instruments: Commitments to originate real estate loans for sale $ 7,433 7,433 — — 7,433 Commitments to sell real estate loans (1,424 ) (1,424 ) — (1,424 ) — Other credit-related commitments (126,811 ) (126,811 ) — — (126,811 ) Interest rate swap agreements used for interest rate risk management (16,924 ) (16,924 ) — (16,924 ) — 12. Fair value measurements, continued December 31, 2018 Carrying Amount Estimated Fair Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 1,605,439 1,605,439 1,528,302 77,137 — Interest-bearing deposits at banks 8,105,197 8,105,197 — 8,105,197 — Trading account assets 185,584 185,584 46,018 139,566 — Investment securities 12,692,813 12,631,656 71,989 12,456,467 103,200 Loans and leases: Commercial loans and leases 22,977,976 22,587,387 — — 22,587,387 Commercial real estate loans 34,363,556 33,832,558 — 346,775 33,485,783 Residential real estate loans 17,154,446 16,974,545 — 3,920,447 13,054,098 Consumer loans 13,970,499 13,819,545 — — 13,819,545 Allowance for credit losses (1,019,444 ) — — — — Loans and leases, net 87,447,033 87,214,035 — 4,267,222 82,946,813 Accrued interest receivable 353,965 353,965 — 353,965 — Financial liabilities: Noninterest-bearing deposits $ (32,256,668 ) (32,256,668 ) — (32,256,668 ) — Savings and interest-checking deposits (50,963,744 ) (50,963,744 ) — (50,963,744 ) — Time deposits (6,124,254 ) (6,201,957 ) — (6,201,957 ) — Deposits at Cayman Islands office (811,906 ) (811,906 ) — (811,906 ) — Short-term borrowings (4,398,378 ) (4,398,378 ) — (4,398,378 ) — Long-term borrowings (8,444,914 ) (8,385,289 ) — (8,385,289 ) — Accrued interest payable (95,274 ) (95,274 ) — (95,274 ) — Trading account liabilities (178,125 ) (178,125 ) — (178,125 ) — Other financial instruments: Commitments to originate real estate loans for sale $ 7,712 7,712 — — 7,712 Commitments to sell real estate loans (6,177 ) (6,177 ) — (6,177 ) — Other credit-related commitments (131,688 ) (131,688 ) — — (131,688 ) Interest rate swap agreements used for interest rate risk management 5,530 5,530 — 5,530 — With the exception of marketable securities, certain off-balance sheet financial instruments and mortgage loans originated for sale, the Company’s financial instruments are not readily marketable and market prices do not exist. The Company, in attempting to comply with the provisions of GAAP that require disclosures of fair value of financial instruments, has not attempted to market its financial instruments to potential buyers, if any exist. Since negotiated prices in illiquid markets depend greatly upon the then present motivations of the buyer and seller, it is reasonable to assume that actual sales prices could vary widely from any estimate of fair value made without the benefit of negotiations. Additionally, changes in market interest rates can dramatically impact the value of financial instruments in a short period of time. The Company does not believe that the estimated information presented herein is representative of the earnings power or value of the Company. The preceding analysis, which is inherently limited in depicting fair value, also does not consider any value associated with existing customer relationships nor the ability of the Company to create value through loan origination, deposit gathering or fee generating activities. Many of the estimates presented herein are based upon the use of highly subjective information and assumptions and, accordingly, the results may not be precise. Management believes that fair value estimates may not be comparable between financial institutions due to the wide range of permitted valuation techniques and numerous estimates which must be made. Furthermore, because the disclosed fair value amounts were estimated as of the balance sheet date, the amounts actually realized or paid upon maturity or settlement of the various financial instruments could be significantly different.

Commitments and contingencies

Commitments and contingencies	3 Months Ended
	Mar. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and contingencies	13. Commitments and contingencies In the normal course of business, various commitments and contingent liabilities are outstanding. The following table presents the Company's significant commitments. Certain of these commitments are not included in the Company's consolidated balance sheet. March 31, December 31, 2019 2018 (In thousands) Commitments to extend credit Home equity lines of credit $ 5,529,111 5,484,197 Commercial real estate loans to be sold 199,722 229,401 Other commercial real estate 7,331,360 7,556,722 Residential real estate loans to be sold 314,402 245,211 Other residential real estate 277,708 219,351 Commercial and other 14,900,142 14,363,803 Standby letters of credit 2,246,864 2,326,991 Commercial letters of credit 59,464 55,808 Financial guarantees and indemnification contracts 3,703,612 3,529,136 Commitments to sell real estate loans 746,307 940,692 Commitments to extend credit are agreements to lend to customers, generally having fixed expiration dates or other termination clauses that may require payment of a fee. In addition to the amounts in the preceding table, the Company had discretionary funding commitments to commercial customers of $8.7 billion and $8.6 billion at March 31, 2019 and December 31, 2018, respectively, that the Company had the unconditional right to cancel prior to funding. Standby and commercial letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. Standby letters of credit generally are contingent upon the failure of the customer to perform according to the terms of the underlying contract with the third party, whereas commercial letters of credit are issued to facilitate commerce and typically result in the commitment being funded when the underlying transaction is consummated between the customer and a third party. The credit risk associated with commitments to extend credit and standby and commercial letters of credit is essentially the same as that involved with extending loans to customers and is subject to normal credit policies. Collateral may be obtained based on management's assessment of the customer's creditworthiness. Financial guarantees and indemnification contracts are oftentimes similar to standby letters of credit and include mandatory purchase agreements issued to ensure that customer obligations are fulfilled, recourse obligations associated with sold loans, and other guarantees of customer performance or compliance with designated rules and regulations. Included in financial guarantees and indemnification contracts are loan principal amounts sold with recourse in conjunction with the Company's involvement in the Fannie Mae Delegated Underwriting and Servicing program. The Company's maximum credit risk for recourse associated with loans sold under this program totaled approximately $3.5 billion and $3.4 billion at March 31, 2019 and December 31, 2018, respectively. Since many loan commitments, standby letters of credit, and guarantees and indemnification contracts expire without being funded in whole or in part, the contract amounts are not necessarily indicative of future cash flows. The Company utilizes commitments to sell real estate loans to hedge exposure to changes in the fair value of real estate loans held for sale. Such commitments are considered derivatives and along with commitments to originate real estate loans to be held for sale are generally recorded in the consolidated balance sheet at estimated fair market value. 13. Commitments and contingencies, continued The Company is contractually obligated to repurchase previously sold residential real estate loans that do not ultimately meet investor sale criteria related to underwriting procedures or loan documentation. When required to do so, the Company may reimburse loan purchasers for losses incurred or may repurchase certain loans. The Company reduces residential mortgage banking revenues by an estimate for losses related to its obligations to loan purchasers. The amount of those charges is based on the volume of loans sold, the level of reimbursement requests received from loan purchasers and estimates of losses that may be associated with previously sold loans. At March 31, 2019, the Company believes that its obligation to loan purchasers was not material to the Company’s consolidated financial position. As previously disclosed, Wilmington Trust Corporation, a wholly-owned subsidiary of M&T, was the subject of a class action lawsuit alleging that Wilmington Trust Corporation’s financial reporting and securities filings prior to its acquisition by M&T in 2011 were in violation of securities laws. In April 2018, the parties reached an agreement in principle and a formal settlement agreement was executed and filed with the court later in the second quarter of 2018. The proposed settlement was preliminarily approved by the court in July 2018. In the first quarter of 2018, the Company increased its reserve for litigation matters in anticipation of the settlement. The settlement amount of $200 million was paid, pursuant to the settlement agreement, during the third quarter of 2018. The settlement agreement was approved by the court in the fourth quarter of 2018. Wilmington Trust, N.A., a wholly owned bank subsidiary of M&T, provides retirement services, including serving in certain trustee roles relating to Employee Stock Ownership Plans (“ESOPs”). Beginning in 2010, the U.S. Department of Labor (“DOL”) announced that it would increase its focus on ESOP transactions, particularly with regard to valuation issues relating to ESOP transactions. Beginning in late 2013, Wilmington Trust, N.A. began receiving requests for information and subpoenas relating to certain ESOP transactions for which it acted as trustee. In June 2016, Wilmington Trust, N.A. received a DOL subpoena seeking information on its global ESOP trustee business. In addition to these investigations, the DOL has commenced three lawsuits against Wilmington Trust, N.A. relating to its role as trustee of three ESOP transactions. Wilmington Trust, N.A. has also been named as a defendant in four private party lawsuits relating to its role as trustee for four ESOP transactions. Under applicable transaction documents, Wilmington Trust, N.A. may be entitled to indemnification by the ESOP Plan Sponsors. The DOL investigations of Wilmington Trust, N.A. and the private party lawsuits could result in civil proceedings, damages, resolutions or settlements, including, among other things, enforcement actions, which could seek or result in damages and/or fines, penalties, restitution, injunctions, enforcement efforts, reputational damage or additional costs and expenses. M&T and its subsidiaries are subject in the normal course of business to various other pending and threatened legal proceedings and matters in which claims for monetary damages are asserted. On an on-going basis management, after consultation with legal counsel, assesses the Company’s liabilities and contingencies in connection with such proceedings. For those matters where it is probable that the Company will incur losses and the amounts of the losses can be reasonably estimated, the Company records an expense and corresponding liability in its consolidated financial statements. The Company increased its recorded liability for legal-related matters by $50 million and $135 million during the three months ended March 31, 2019 and 2018, respectively. To the extent pending or threatened litigation could result in exposure in excess of the recorded liability, the amount of such excess is not currently estimable. Although not considered probable, the range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability, was estimated to be between $0 and $100 million as of March 31, 2019. Although the Company does not believe that the outcome of pending legal matters will be material to the Company’s consolidated financial position, it cannot rule out the possibility that such outcomes will be material to the consolidated results of operations for a particular reporting period in the future.

Segment information

Segment information	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Segment information	14. Segment information Reportable segments have been determined based upon the Company's internal profitability reporting system, which is organized by strategic business unit. Certain strategic business units have been combined for segment information reporting purposes where the nature of the products and services, the type of customer and the distribution of those products and services are similar. The reportable segments are Business Banking, Commercial Banking, Commercial Real Estate, Discretionary Portfolio, Residential Mortgage Banking and Retail Banking. The financial information of the Company's segments was compiled utilizing the accounting policies described in note 22 of Notes to Financial Statements in the 2018 Annual Report. The management accounting policies and processes utilized in compiling segment financial information are highly subjective and, unlike financial accounting, are not based on authoritative guidance similar to GAAP. As a result, the financial information of the reported segments is not necessarily comparable with similar information reported by other financial institutions. Furthermore, changes in management structure or allocation methodologies and procedures may result in changes in reported segment financial data. Information about the Company's segments is presented in the following table: Three Months Ended March 31 2019 2018 Total Revenues(a) Inter- segment Revenues Net Income (Loss) Total Revenues(a) Inter- segment Revenues Net Income (Loss) (In thousands) Business Banking $ 139,322 856 43,271 $ 127,884 918 37,718 Commercial Banking 267,490 840 132,218 266,396 850 125,465 Commercial Real Estate 219,173 354 117,498 202,607 340 108,303 Discretionary Portfolio 63,917 (9,299 ) 39,172 50,038 (10,832 ) 19,739 Residential 83,761 14,514 12,941 82,458 15,421 14,946 Retail Banking 430,891 2,511 145,066 393,476 2,865 123,380 All Other 346,271 (9,776 ) (7,424 ) 311,354 (9,562 ) (76,941 ) Total $ 1,550,825 — 482,742 $ 1,434,213 — 352,610 Average Total Assets Three Months Ended March 31 Year Ended December 31 2019 2018 2018 (In millions) Business Banking $ 5,702 5,681 5,631 Commercial Banking 27,858 26,482 26,626 Commercial Real Estate 23,572 22,811 22,885 Discretionary Portfolio 30,341 34,095 32,123 Residential Mortgage Banking 2,071 2,278 2,161 Retail Banking 14,403 13,377 13,656 All Other 12,892 12,960 13,877 Total $ 116,839 117,684 116,959 (a) Total revenues are comprised of net interest income and other income. Net interest income is the difference between taxable-equivalent interest earned on assets and interest paid on liabilities owed by a segment and a funding charge (credit) based on the Company's internal funds transfer and allocation methodology. Segments are charged a cost to fund any assets (e.g. loans) and are paid a funding credit for any funds provided (e.g. deposits). The taxable-equivalent adjustment aggregated $5,967,000 and $4,809,000 for the three-month periods ended March 31, 2019 and 2018, respectively, and is eliminated in "All Other" total revenues. Intersegment revenues are included in total revenues of the reportable segments. The elimination of intersegment revenues is included in the determination of "All Other" total revenues

Relationship with Bayview Lendi

Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P.	3 Months Ended
	Mar. 31, 2019
Text Block [Abstract]
Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P.	15. Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P. M&T holds a 20% minority interest in Bayview Lending Group LLC ("BLG"), a privately-held commercial mortgage company. M&T recognizes income or loss from BLG using the equity method of accounting. That investment had no remaining carrying value Bayview Financial Holdings, L.P. (together with its affiliates, "Bayview Financial"), a privately-held specialty finance company, is BLG's majority investor. In addition to their common investment in BLG, the Company and Bayview Financial conduct other business activities with each other. The Company has obtained loan servicing rights for mortgage loans from BLG and Bayview Financial having outstanding principal balances of $2.5 billion at each of March 31, 2019 and December 31, 2018. Revenues from those servicing rights were $3 million and $4 million for the three-month periods ended March 31, 2019 and 2018, respectively. The Company sub-services residential mortgage loans for Bayview Financial having outstanding principal balances of $54.9 billion and $56.8 billion at March 31, 2019 and December 31, 2018, respectively. Revenues earned for sub-servicing loans for Bayview Financial were $28 million and $30 million for the three-month periods ended March 31, 2019 and 2018, respectively, In addition, the Company held $108 million and $113 million of mortgage-backed securities in its held-to-maturity portfolio at March 31, 2019 and December 31, 2018, respectively, that were securitized by Bayview Financial. At March 31, 2019, the Company held $94 million of Bayview Financial’s $738 million syndicated loan facility. On January 31, 2019, the Company and Bayview Financial entered into an arrangement whereby the Company would add approximately $7.9 billion to its residential mortgage loan sub-servicing portfolio, effective April 2, 2019.

Recent accounting developments

Recent accounting developments	3 Months Ended
	Mar. 31, 2019
Accounting Changes And Error Corrections [Abstract]
Recent accounting developments	16. Recent accounting developments The following table provides a description of accounting standards that were adopted by the Company in 2019 as well as standards that are not effective that could have an impact to M&T’s consolidated financial statements upon adoption. Standard Description Required date of adoption Effect on consolidated financial statements Standards Adopted in 2019 Leases The new guidance requires lessees to record a right-of-use asset and a lease liability for all leases with a term greater than 12 months. While the guidance requires all leases to be recognized in the balance sheet, there continues to be a differentiation between finance leases and operating leases for purposes of income statement recognition and cash flow statement presentation. For finance leases, interest on the lease liability and amortization of the right-of-use asset will be recognized separately in the statement of income. Repayments of principal on those lease liabilities will be classified within financing activities and payments of interest on the lease liability will be classified within operating activities in the statement of cash flows. For operating leases, a single lease cost is recognized in the statement of income and allocated over the lease term, generally on a straight-line basis. All cash payments are presented within operating activities in the statement of cash flows. The accounting applied by lessors is largely unchanged from existing GAAP, however, the guidance eliminates the accounting model for leveraged leases for leases that commence after the effective date of the guidance. January 1, 2019 Early adoption permitted The Company adopted the guidance on January 1, 2019 and applied the guidance retrospectively at the beginning of the period of adoption. The Company occupies certain banking offices and uses certain equipment under noncancelable operating lease agreements which prior to the adoption of the guidance were not reflected in its consolidated balance sheet. Upon adoption, the Company recognized a right-of-use asset of $394 million and increased liabilities by $399 million as a result of recognizing lease liabilities in its consolidated balance sheet. The new guidance did not have a material impact on the Company’s consolidated statement of income. Premium Amortization on Purchased Callable Debt Securities The amended guidance requires the premium on callable debt securities to be amortized to the earliest call date. The amendments do not require an accounting change for securities held at a discount; the discount continues to be amortized to maturity. January 1, 2019 Early adoption permitted The Company adopted the amended guidance effective January 1, 2019 and applied the modified retrospective approach for reporting purposes. The adoption did not have a material effect on the Company’s consolidated financial position nor on its results of operations. 16. Recent accounting developments, continued Standard Description Required date of adoption Effect on consolidated financial statements Standards Not Yet Adopted as of March 31, 2019 Measurement of Credit Losses on Financial Instruments The amended guidance replaces the current incurred loss model for determining the allowance for credit losses. The guidance requires financial assets measured at amortized cost to be presented at the net amount expected to be collected. The allowance for credit losses will represent a valuation account that is deducted from the amortized cost basis of the financial assets to present their net carrying value at the amount expected to be collected. The income statement will reflect the measurement of credit losses for newly recognized financial assets as well as expected increases or decreases of expected credit losses that have taken place during the period. When determining the allowance, expected credit losses over the contractual term of the financial asset(s) (taking into account prepayments) will be estimated considering relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectibility of the reported amount. The amended guidance also requires recording an allowance for credit losses for purchased financial assets with a more-than-insignificant amount of credit deterioration since origination. The initial allowance for these assets will be added to the purchase price at acquisition rather than being reported as an expense. Subsequent changes in the allowance will be recorded through the income statement as an expense adjustment. In addition, the amended guidance requires credit losses relating to available-for-sale debt securities to be recorded through an allowance for credit losses. The calculation of credit losses for available-for-sale securities will be similar to how it is determined under existing guidance. January 1, 2020 Early adoption permitted as of January 1, 2019 The Company is continuing the development of its approach for determining expected credit losses under the new guidance. The Company has a cross-functional implementation team working on model development, model validation, and development of a qualitative framework, data sourcing, and technology enhancements. The Company expects that the new guidance will result in an increase in its allowance for credit losses as a result of considering credit losses over the expected life of its loan portfolios, in particular its consumer and residential real estate loan portfolios. Increases in the level of allowances will reflect new requirements to include the nonaccretable principal difference on purchased credit impaired loans and estimated credit losses on investment securities classified as held-to-maturity, if any. The expected changes to the allowance for credit losses and the impact to the Company’s financial statements are still to be determined. The amount of the change will be affected by economic conditions, reasonable forecasts of such conditions and the composition of the Company’s portfolio as of the date of adoption. Simplifying the Test for Goodwill Impairment The amended guidance eliminates step 2 from the goodwill impairment test. January 1, 2020 Early adoption permitted The amendments should be applied using a prospective transition method. The Company does not expect the guidance will have a material impact on its consolidated financial statements, unless at some point in the future one of its reporting units were to fail step 1 of the goodwill impairment test. 16. Recent accounting developments, continued Standard Description Required date of adoption Effect on consolidated financial statements Standards Not Yet Adopted as of March 31, 2019 Changes to the Disclosure Requirements for Fair Value Measurements The amended guidance modifies the disclosure requirements on fair value measurements in Topic 820, Fair Value Measurements. The amendments are a result of the disclosure framework project that focuses on improvements to the effectiveness of disclosures in the notes to financial statements. The amendments remove, modify, and add certain disclosure requirements. The disclosure requirements being removed relating to public companies are (1) the amount and reason for transfers between Level 1 and Level 2 of the fair value hierarchy, (2) the policy for timing of transfers between levels, and (3) the valuation process for Level 3 fair value measurements. The disclosure requirements being modified relating to public companies are (1) for investments in certain entities that calculate net asset value, an entity is required to disclose the timing of liquidation of an investee’s asset and the date when restrictions from redemption might lapse only if the investee has communicated the timing to the entity or announced the timing publicly, and (2) the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as a result of the use of unobservable inputs. The disclosure requirements being added relating to public companies are (1) to disclose the changes in unrealized gains and losses for the period for recurring Level 3 fair value measurements, and (2) to disclose the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. January 1, 2020 Early adoption permitted The amendments relating to changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurements uncertainty should be applied prospectively. All other amendments should be applied retrospectively. The Company does not expect the guidance to have a material impact on its consolidated financial statements. Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract The amended guidance requires a hosting arrangement that is a service contract to follow the guidance in Subtopic 350-40 to determine which implementation costs to capitalize and which costs to expense. January 1, 2020 Early adoption permitted The amendments should be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. The Company is evaluating the impact that the guidance will have on its consolidated financial statements. 16. Recent accounting developments, continued Standard Description Required date of adoption Effect on consolidated financial statements Standards Not Yet Adopted as of March 31, 2019 Improvements to Related Party Guidance for VIEs The amended guidance requires that indirect interests held through related parties in common control arrangements should be considered on a proportional basis for determining whether fees paid to decision makers and service providers are variable interests. January 1, 2020 Early adoption permitted The amendments should be applied retrospectively with a cumulative-effect adjustment to retained earnings at the beginning of the earliest period presented. The Company does not expect the guidance to have a material impact on its consolidated financial statements. Changes to the Disclosure Requirements for Defined Benefit Plans The amended guidance modifies the disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. The amendments are a result of the disclosure framework project that focuses on improvements to the effectiveness of disclosures in the notes to financial statements. The amendments remove and add certain disclosure requirements. The disclosure requirements being removed relating to public companies are (1) the amounts in accumulated other comprehensive income expected to be recognized as components of net periodic benefit cost over the next fiscal year, (2) the amount and timing of plan assets expected to be returned to the employer, (3) the 2001 disclosure requirement relating to Japanese Welfare Pension Insurance Law, (4) related party disclosures about the amount of future annual benefits covered by insurance, and (5) the effects of a one-percentage-point change in assumed health care cost trends on the benefit cost and obligation. The disclosure requirements being added relating to public companies are (1) the weighted-average interest crediting rates for cash balance plans , and (2) an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period. January 1, 2021 Early adoption permitted The amendments should be applied retrospectively. The Company does not expect the guidance to have a material impact on its consolidated financial statements.

Significant accounting polici_2

Significant accounting policies (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Basis of Accounting	The consolidated interim financial statements of M&T Bank Corporation (“M&T”) and subsidiaries (“the Company”) were compiled in accordance with generally accepted accounting principles (“GAAP”) using the accounting policies set forth in note 1 of Notes to Financial Statements included in Form 10-K for the year ended December 31, 2018 (“2018 Annual Report”), except that effective January 1, 2019 the Company adopted accounting guidance that is discussed in notes 3, 4 and 16 herein. The financial statements contain all adjustments which are, in the opinion of management, necessary for a fair statement of the Company’s financial position, results of operations and cash flows for the interim periods presented.

Investment securities (Tables)

Investment securities (Tables)	3 Months Ended
	Mar. 31, 2019
Investments Debt And Equity Securities [Abstract]
Amortized Cost and Estimated Fair Value of Investment Securities	The amortized cost and estimated fair value of investment securities were as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (In thousands) March 31, 2019 Investment securities available for sale: U.S. Treasury and federal agencies $ 1,144,288 $ 4 $ 4,864 $ 1,139,428 Obligations of states and political subdivisions 1,181 4 4 1,181 Mortgage-backed securities: Government issued or guaranteed 7,115,459 29,959 91,511 7,053,907 Privately issued 16 — — 16 Other debt securities 137,742 1,249 7,939 131,052 8,398,686 31,216 104,318 8,325,584 Investment securities held to maturity: U.S. Treasury and federal agencies 944,230 735 15 944,950 Obligations of states and political subdivisions 6,810 27 — 6,837 Mortgage-backed securities: Government issued or guaranteed 2,652,219 11,876 19,472 2,644,623 Privately issued 107,858 12,806 21,060 99,604 Other debt securities 3,582 — — 3,582 3,714,699 25,444 40,547 3,699,596 Total debt securities $ 12,113,385 $ 56,660 $ 144,865 $ 12,025,180 Equity and other securities: Readily marketable equity — at fair value $ 48,261 $ 28,913 $ 588 $ 76,586 Other — at cost 419,971 — — 419,971 Total equity and other securities $ 468,232 $ 28,913 $ 588 $ 496,557 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (In thousands) December 31, 2018 Investment securities available for sale: U.S. Treasury and federal agencies $ 1,346,782 $ — $ 9,851 $ 1,336,931 Obligations of states and political subdivisions 1,660 4 5 1,659 Mortgage-backed securities: Government issued or guaranteed 7,383,340 15,754 182,103 7,216,991 Privately issued 24 — 2 22 Other debt securities 137,617 770 11,481 126,906 8,869,423 16,528 203,442 8,682,509 Investment securities held to maturity: U.S. Treasury and federal agencies 446,542 — 239 446,303 Obligations of states and political subdivisions 7,494 22 12 7,504 Mortgage-backed securities: Government issued or guaranteed 2,745,776 4,165 55,111 2,694,830 Privately issued 113,160 12,345 22,327 103,178 Other debt securities 3,668 — — 3,668 3,316,640 16,532 77,689 3,255,483 Total debt securities $ 12,186,063 $ 33,060 $ 281,131 $ 11,937,992 Equity and other securities: Readily marketable equity — at fair value $ 77,440 $ 17,295 $ 818 $ 93,917 Other — at cost 599,747 — — 599,747 Total equity and other securities $ 677,187 $ 17,295 $ 818 $ 693,664
Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity	At March 31, 2019, the amortized cost and estimated fair value of debt securities by contractual maturity were as follows: Amortized Cost Estimated Fair Value (In thousands) Debt securities available for sale: Due in one year or less $ 1,141,640 1,136,864 Due after one year through five years 9,470 9,355 Due after five years through ten years 102,101 99,642 Due after ten years 30,000 25,800 1,283,211 1,271,661 Mortgage-backed securities available for sale 7,115,475 7,053,923 $ 8,398,686 8,325,584 Debt securities held to maturity: Due in one year or less $ 947,176 947,905 Due after one year through five years 3,864 3,882 Due after ten years 3,582 3,582 954,622 955,369 Mortgage-backed securities held to maturity 2,760,077 2,744,227 $ 3,714,699 3,699,596
Investment Securities in Continuous Unrealized Loss Position	A summary of investment securities that as of March 31, 2019 and December 31, 2018 had been in a continuous unrealized loss position for less than twelve months and those that had been in a continuous unrealized loss position for twelve months or longer follows: Less Than 12 Months 12 Months or More Fair Value Unrealized Losses Fair Value Unrealized Losses (In thousands) March 31, 2019 Investment securities available for sale: U.S. Treasury and federal agencies $ 274 (1 ) 1,137,550 (4,863 ) Obligations of states and political subdivisions — — 507 (4 ) Mortgage-backed securities: Government issued or guaranteed 18,447 (111 ) 5,076,762 (91,400 ) Other debt securities 36,500 (294 ) 67,662 (7,645 ) 55,221 (406 ) 6,282,481 (103,912 ) Investment securities held to maturity: U.S. Treasury and federal agencies 249,082 (15 ) — — Mortgage-backed securities: Government issued or guaranteed — — 1,620,580 (19,472 ) Privately issued — — 51,091 (21,060 ) 249,082 (15 ) 1,671,671 (40,532 ) Total $ 304,303 (421 ) 7,954,152 (144,444 ) December 31, 2018 Investment securities available for sale: U.S. Treasury and federal agencies $ 273 (2 ) 1,335,559 (9,849 ) Obligations of states and political subdivisions 629 (5 ) — — Mortgage-backed securities: Government issued or guaranteed 405,558 (2,892 ) 5,646,773 (179,211 ) Privately issued 22 (2 ) — — Other debt securities 53,478 (2,187 ) 66,014 (9,294 ) 459,960 (5,088 ) 7,048,346 (198,354 ) Investment securities held to maturity: U.S. Treasury and federal agencies 446,303 (239 ) — — Obligations of states and political subdivisions — — 3,126 (12 ) Mortgage-backed securities: Government issued or guaranteed 179,354 (989 ) 2,082,723 (54,122 ) Privately issued — — 51,943 (22,327 ) 625,657 (1,228 ) 2,137,792 (76,461 ) Total $ 1,085,617 (6,316 ) 9,186,138 (274,815 )

Loans and leases and the allo_2

Loans and leases and the allowance for credit losses (Tables)	3 Months Ended
	Mar. 31, 2019
Receivables [Abstract]
Summary of Current, Past Due and Nonaccrual Loans	A summary of current, past due and nonaccrual loans as of March 31, 2019 and December 31, 2018 follows: Current 30-89 Days Past Due Accruing Loans Due 90 Days or More (a) Accruing Loans Acquired a Discount Past Due 90 days or More (b) Purchased Impaired (c) Nonaccrual Total (In thousands) March 31, 2019 Commercial, financial, leasing, etc. $ 22,701,500 141,555 1,047 283 — 245,819 $ 23,090,204 Real estate: Commercial 25,441,419 159,209 7,394 158 10,305 207,709 25,826,194 Residential builder and developer 1,738,846 2,190 — — 549 4,392 1,745,977 Other commercial construction 7,036,036 31,152 31,032 — 640 19,899 7,118,759 Residential 13,337,558 406,106 199,940 6,425 187,631 210,266 14,347,926 Residential — limited documentation 2,186,132 71,354 — — 79,658 84,863 2,422,007 Consumer: Home equity lines and loans 4,634,634 31,145 — 4,871 — 69,245 4,739,895 Recreational finance 4,295,732 22,549 — 235 — 10,972 4,329,488 Automobile 3,619,015 62,846 — — — 21,209 3,703,070 Other 1,257,839 14,420 4,844 32,023 — 7,237 1,316,363 Total $ 86,248,711 942,526 244,257 43,995 278,783 881,611 $ 88,639,883 December 31, 2018 Commercial, financial, leasing, etc. $ 22,701,020 39,798 2,567 168 — 234,423 $ 22,977,976 Real estate: Commercial 25,250,983 134,474 11,457 10 9,769 203,672 25,610,365 Residential builder and developer 1,665,178 20,333 — — — 4,798 1,690,309 Other commercial construction 6,982,077 43,615 14,344 — 641 22,205 7,062,882 Residential 13,591,790 404,808 189,682 6,650 203,044 233,352 14,629,326 Residential — limited documentation 2,278,040 72,544 — — 89,851 84,685 2,525,120 Consumer: Home equity lines and loans 4,758,513 25,416 — 5,033 — 71,292 4,860,254 Recreational finance 4,085,781 29,947 — 235 — 11,199 4,127,162 Automobile 3,555,757 79,804 — — — 23,359 3,658,920 Other 1,271,811 15,598 4,477 27,654 — 4,623 1,324,163 Total $ 86,140,950 866,337 222,527 39,750 303,305 893,608 $ 88,466,477 (a) Excludes loans acquired at a discount. (b) Loans acquired at a discount that were recorded at fair value at acquisition date. This category does not include purchased impaired loans that are presented separately. (c) Accruing loans acquired at a discount that were impaired at acquisition date and recorded at fair value.
Outstanding Principal Balance and Carrying Amount of Loans and Included in Consolidated Balance Sheet	The outstanding principal balance and the carrying amount of loans acquired at a discount that were recorded at fair value at the acquisition date and included in the consolidated balance sheet were as follows: March 31, December 31, 2019 2018 (In thousands) Outstanding principal balance $ 960,990 $ 1,016,785 Carrying amount: Commercial, financial, leasing, etc. 25,060 27,073 Commercial real estate 125,310 135,047 Residential real estate 442,260 473,511 Consumer 93,486 91,860 $ 686,116 $ 727,491
Summary of Changes in Accretable Yield for Acquired Loans	A summary of changes in the accretable yield for loans acquired at a discount for the three months ended March 31, 2019 and 2018 follows: Three Months Ended March 31 2019 2018 Purchased Other Purchased Other Impaired Acquired Impaired Acquired (In thousands) Balance at beginning of period $ 147,210 $ 96,907 $ 157,918 $ 133,162 Interest income (18,082 ) (9,717 ) (9,819 ) (15,112 ) Reclassifications from nonaccretable balance 11,189 4,865 908 207 Other (a) — 1,632 — (73 ) Balance at end of period $ 140,317 $ 93,687 $ 149,007 $ 118,184 (a) Other changes in expected cash flows including changes in interest rates and prepayment assumptions.
Changes in Allowance for Credit Losses	Changes in the allowance for credit losses for the three months ended March 31, 2019 were as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Unallocated Total (In thousands) Beginning balance $ 330,055 341,655 69,125 200,564 78,045 $ 1,019,444 Provision for credit losses 6,271 (4,203 ) (2,447 ) 22,883 (504 ) 22,000 Net charge-offs Charge-offs (8,500 ) (283 ) (3,372 ) (32,945 ) — (45,100 ) Recoveries 7,794 826 1,830 12,543 — 22,993 Net (charge-offs) recoveries (706 ) 543 (1,542 ) (20,402 ) — (22,107 ) Ending balance $ 335,620 337,995 65,136 203,045 77,541 $ 1,019,337 Changes in the allowance for credit losses for the three months ended March 31, 2018 were as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Unallocated Total (In thousands) Beginning balance $ 328,599 374,085 65,405 170,809 78,300 $ 1,017,198 Provision for credit losses 7,230 (5,225 ) 10,486 29,814 695 43,000 Net charge-offs Charge-offs (14,581 ) (1,366 ) (4,354 ) (36,451 ) — (56,752 ) Recoveries 4,823 223 1,510 9,669 — 16,225 Net (charge-offs) recoveries (9,758 ) (1,143 ) (2,844 ) (26,782 ) — (40,527 ) Ending balance $ 326,071 367,717 73,047 173,841 78,995 $ 1,019,671
Impaired Loans and Leases	I nformation with respect to loans and leases that were considered impaired as of March 31, 2019 and December 31, 2018 and for the three-month periods ended March 31, 2019 and 2018 follows. March 31, 2019 December 31, 2018 Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance (In thousands) With an allowance recorded: Commercial, financial, leasing, etc. $ 201,337 220,116 50,192 153,478 175,549 46,034 Real estate: Commercial 102,247 119,062 10,449 110,253 125,117 11,937 Residential builder and developer 6,805 7,399 327 5,981 6,557 462 Other commercial construction 10,696 13,624 703 10,563 11,113 640 Residential 121,351 142,872 5,291 124,974 147,817 5,402 Residential — limited documentation 71,113 86,276 3,000 74,156 90,066 3,000 Consumer: Home equity lines and loans 47,363 52,583 9,025 47,982 53,248 9,135 Recreational finance 5,539 5,740 1,147 6,138 9,163 1,261 Automobile 3,522 3,603 729 3,527 3,599 729 Other 5,612 11,902 1,128 5,203 8,380 1,046 575,585 663,177 81,991 542,255 630,609 79,646 With no related allowance recorded: Commercial, financial, leasing, etc. 91,355 97,342 — 105,507 136,128 — Real estate: Commercial 125,289 138,095 — 113,376 124,657 — Residential builder and developer 2,756 2,781 — 2,593 2,602 — Other commercial construction 9,203 9,432 — 11,710 11,880 — Residential 19,535 25,771 — 15,379 20,496 — Residential — limited documentation 6,145 10,434 — 5,631 9,796 — 254,283 283,855 — 254,196 305,559 — Total: Commercial, financial, leasing, etc. 292,692 317,458 50,192 258,985 311,677 46,034 Real estate: Commercial 227,536 257,157 10,449 223,629 249,774 11,937 Residential builder and developer 9,561 10,180 327 8,574 9,159 462 Other commercial construction 19,899 23,056 703 22,273 22,993 640 Residential 140,886 168,643 5,291 140,353 168,313 5,402 Residential — limited documentation 77,258 96,710 3,000 79,787 99,862 3,000 Consumer: Home equity lines and loans 47,363 52,583 9,025 47,982 53,248 9,135 Recreational finance 5,539 5,740 1,147 6,138 9,163 1,261 Automobile 3,522 3,603 729 3,527 3,599 729 Other 5,612 11,902 1,128 5,203 8,380 1,046 Total $ 829,868 947,032 81,991 796,451 936,168 79,646
Interest Income Recognized on Impaired Loans	Three Months Ended March 31, 2019 Three Months Ended March 31, 2018 Interest Income Recognized Interest Income Recognized Average Recorded Investment Total Cash Basis Average Recorded Investment Total Cash Basis (In thousands) Commercial, financial, leasing, etc. $ 265,248 3,038 3,038 272,172 783 783 Real estate: Commercial 225,374 1,091 1,091 181,846 3,147 3,147 Residential builder and developer 8,875 115 115 9,840 1,682 1,682 Other commercial construction 20,398 564 564 10,102 6 6 Residential 140,403 2,022 666 121,209 1,902 902 Residential — limited documentation 78,238 1,353 208 85,595 1,728 696 Consumer: Home equity lines and loans 47,556 416 62 48,797 414 86 Recreational finance 6,023 142 4 1,458 63 2 Automobile 3,530 54 19 13,125 224 15 Other 5,218 122 4 1,661 22 1 Total $ 800,863 8,917 5,771 745,805 9,971 7,320
Summary of Loan Grades	The following table summarizes the loan grades applied to the various classes of the Company’s commercial loans and commercial real estate loans. Real Estate Commercial, Residential Other Financial, Builder and Commercial Leasing, etc. Commercial Developer Construction (In thousands) March 31, 2019 Pass $ 21,734,455 24,686,100 1,535,068 6,870,882 Criticized accrual 1,109,930 932,385 206,517 227,978 Criticized nonaccrual 245,819 207,709 4,392 19,899 Total $ 23,090,204 25,826,194 1,745,977 7,118,759 December 31, 2018 Pass $ 21,693,705 24,539,706 1,546,002 6,890,562 Criticized accrual 1,049,848 866,987 139,509 150,115 Criticized nonaccrual 234,423 203,672 4,798 22,205 Total $ 22,977,976 25,610,365 1,690,309 7,062,882
Allocation of Allowance for Credit Losses on Basis of Company's Impairment Methodology	The allocation of the allowance for credit losses summarized on the basis of the Company’s impairment methodology was as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Total (In thousands) March 31, 2019 Individually evaluated for impairment $ 50,192 11,479 8,291 12,029 $ 81,991 Collectively evaluated for impairment 285,428 326,516 47,028 191,016 849,988 Purchased impaired — — 9,817 — 9,817 Allocated $ 335,620 337,995 65,136 203,045 941,796 Unallocated 77,541 Total $ 1,019,337 December 31, 2018 Individually evaluated for impairment $ 46,034 13,039 8,402 12,171 $ 79,646 Collectively evaluated for impairment 284,021 328,616 48,326 188,393 849,356 Purchased impaired — — 12,397 — 12,397 Allocated $ 330,055 341,655 69,125 200,564 941,399 Unallocated 78,045 Total $ 1,019,444
Recorded Investment in Loans and Leases on Basis of Company's Impairment Methodology	The recorded investment in loans and leases summarized on the basis of the Company’s impairment methodology was as follows: Commercial, Financial, Real Estate Leasing, etc. Commercial Residential Consumer Total (In thousands) March 31, 2019 Individually evaluated for impairment $ 292,692 256,996 218,144 62,036 $ 829,868 Collectively evaluated for impairment 22,797,512 34,422,440 16,284,500 14,026,780 87,531,232 Purchased impaired — 11,494 267,289 — 278,783 Total $ 23,090,204 34,690,930 16,769,933 14,088,816 $ 88,639,883 December 31, 2018 Individually evaluated for impairment $ 258,985 254,476 220,140 62,850 $ 796,451 Collectively evaluated for impairment 22,718,991 34,098,670 16,641,411 13,907,649 87,366,721 Purchased impaired — 10,410 292,895 — 303,305 Total $ 22,977,976 34,363,556 17,154,446 13,970,499 $ 88,466,477
Loan Modification Activities that were Considered Troubled Debt Restructurings	The table that follows summarizes the Company’s loan modification activities that were considered troubled debt restructurings for the three-month periods ended March 31, 2019 and 2018: Post-modification (a) Number Pre- modification Recorded Investment Principal Deferral Interest Rate Reduction Combination of Concession Types Total Three Months Ended March 31, 2019 (Dollars in thousands) Commercial, financial, leasing, etc. 65 $ 30,615 $ 6,474 $ — $ 24,270 $ 30,744 Real estate: Commercial 15 9,241 987 — 7,967 8,954 Residential builder and developer 2 1,330 1,068 — — 1,068 Other commercial construction 1 418 — — 366 366 Residential 17 3,816 1,751 — 2,273 4,024 Residential — limited documentation 1 236 239 — — 239 Consumer: Home equity lines and loans 7 476 37 — 454 491 Recreational finance 4 88 88 — — 88 Automobile 20 317 280 — 37 317 Total 132 $ 46,537 $ 10,924 $ — $ 35,367 $ 46,291 Three Months Ended March 31, 2018 Commercial, financial, leasing, etc. 56 $ 47,994 $ 35,673 $ 624 $ 13,047 $ 49,344 Real estate: Commercial 20 6,780 5,824 — 927 6,751 Other commercial construction 1 752 746 — — 746 Residential 47 12,636 6,945 — 6,902 13,847 Residential — limited documentation 2 295 267 — 118 385 Consumer: Home equity lines and loans 14 1,348 4 — 1,348 1,352 Recreational finance 2 49 49 — — 49 Automobile 8 148 148 — — 148 Total 150 $ 70,002 $ 49,656 $ 624 $ 22,342 $ 72,622 (a) Financial effects impacting the recorded investment included principal payments or advances, charge-offs and capitalized escrow arrearages. The present value of interest rate concessions, discounted at the effective rate of the original loan, was not material.
Summary of Lease Financing Receivables	A summary of lease financing receivables follows: March 31, December 31, 2019 2018 (In thousands) Commercial leases: Direct financings: Lease payments receivable $ 1,140,794 $ 1,155,464 Estimated residual value of leased assets 82,686 85,169 Unearned income (106,797 ) (110,458 ) Investment in direct financings 1,116,683 1,130,175 Leveraged leases: Lease payments receivable 82,841 85,007 Estimated residual value of leased assets 81,261 81,261 Unearned income (33,273 ) (33,717 ) Investment in leveraged leases 130,829 132,551 Total investment in leases $ 1,247,512 $ 1,262,726 Deferred taxes payable arising from leveraged leases $ 73,808 $ 74,995
Minimum Future Lease Payments to be Received from Lease Financings	At March 31, 2019, the minimum future lease payments to be received from lease financings were as follows: (In thousands) Twelve-month period ending March 31: 2020 $ 322,403 2021 302,912 2022 220,516 2023 148,313 2024 84,610 Later years 144,881 $ 1,223,635

Operating Leases (Tables)

Operating Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Summary of Right-of-Use Assets Recognized as Component of Premises and Equipment and Lease Liabilities Recognized as Component of Accrued Interest and Other Liabilities in Consolidated Balance Sheet	As of March 31, 2019, the Company reported right-of-use assets recognized as a component of “premises and equipment” and lease liabilities recognized as a component of “accrued interest and other liabilities” in the consolidated balance sheet, as follows: March 31, 2019 (In thousands) Right-of-use assets $ 392,847 Lease liabilities 419,958
Summary of Lease Costs for Operating Leases, Cash Paid Toward Lease Liabilities, and Weighted-Average Remaining Term and Discount Rates of Operating Leases	The following table presents information about the Company’s lease costs for operating leases recorded in the consolidated balance sheet, cash paid toward lease liabilities, and the weighted-average remaining term and discount rates of the operating leases. Three Months Ended March 31, 2019 (Dollars in thousands) Lease cost Operating lease cost $ 24,639 Short-term lease cost 34 Variable lease cost 466 Sublease income (1,917 ) Total net lease cost $ 23,222 Other information Right-of-use assets obtained in exchange for new operating lease liabilities $ 20,410 Cash paid toward lease liabilities 25,656 Weighted-average remaining lease term 7 years Weighted-average discount rate 3.2 %
Summary of Minimum Lease Payments Under Noncancelable Operating Leases	Minimum lease payments under noncancelable operating leases are summarized in the following table. These minimum lease payments are not materially different from those reported in the 2018 Annual Report. (In thousands) Twelve-month period ending March 31: 2020 $ 93,460 2021 87,025 2022 71,369 2023 58,847 2024 41,034 Later years 111,683 Total lease payments $ 463,418 Less: imputed interest 43,460 Total $ 419,958

Revenue from contracts with c_2

Revenue from contracts with customers (Tables)	3 Months Ended
	Mar. 31, 2019
ASU 2014-09 [Member]
Summary of Sources of Noninterest Income that are Subject to Noted Accounting Guidance	The following tables summarize sources of the Company’s noninterest income during the three-month periods ended March 31, 2019 and 2018 that are subject to the noted accounting guidance. Business Banking Commercial Banking Commercial Real Estate Discretionary Portfolio Residential Mortgage Banking Retail Banking All Other Total Three Months Ended March 31, 2019 (In thousands) Classification in consolidated statement of income Service charges on deposit accounts $ 15,109 23,210 2,526 — 2 61,151 1,114 $ 103,112 Trust income 5 214 — — — — 132,567 132,786 Brokerage services income — — — — — — 12,476 12,476 Other revenues from operations: Merchant discount and credit card fees 8,882 12,092 606 — — 3,138 420 25,138 Other — 1,002 1,788 401 1,064 8,494 10,488 23,237 $ 23,996 36,518 4,920 401 1,066 72,783 157,065 $ 296,749 Three Months Ended March 31, 2018 Classification in consolidated statement of income Service charges on deposit accounts $ 15,404 24,654 2,764 — 3 60,601 1,689 $ 105,115 Trust income — — — — — — 131,375 131,375 Brokerage services income — — — — — — 13,392 13,392 Other revenues from operations: Merchant discount and credit card fees 7,503 12,712 554 — — 3,388 615 24,772 Other — 1,563 859 452 1,043 9,865 9,108 22,890 $ 22,907 38,929 4,177 452 1,046 73,854 156,179 $ 297,544

Pension plans and other postr_2

Pension plans and other postretirement benefits (Tables)	3 Months Ended
	Mar. 31, 2019
Compensation And Retirement Disclosure [Abstract]
Net Periodic Defined Benefit Cost for Defined Benefit Plans	Net periodic defined benefit cost for defined benefit plans consisted of the following: Pension Benefits Other Postretirement Benefits Three Months Ended March 31 2019 2018 2019 2018 (In thousands) Service cost $ 4,087 5,103 200 226 Interest cost on projected benefit obligation 20,200 18,805 603 557 Expected return on plan assets (30,600 ) (30,875 ) — — Amortization of prior service cost (credit) 125 125 (1,175 ) (1,175 ) Amortization of net actuarial loss (gain) 4,450 11,100 (300 ) (200 ) Net periodic cost (benefit) $ (1,738 ) 4,258 (672 ) (592 )

Earnings per common share (Tabl

Earnings per common share (Tables)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Computations of Basic Earnings Per Common Share	The computations of basic earnings per common share follow: Three Months Ended March 31 2019 2018 (In thousands, except per share) Income available to common shareholders: Net income $ 482,742 352,610 Less: Preferred stock dividends (a) (18,130 ) (18,130 ) Net income available to common equity 464,612 334,480 Less: Income attributable to unvested stock-based compensation awards (2,526 ) (1,732 ) Net income available to common shareholders $ 462,086 332,748 Weighted-average shares outstanding: Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards 138,637 149,470 Less: Unvested stock-based compensation awards (748 ) (782 ) Weighted-average shares outstanding 137,889 148,688 Basic earnings per common share $ 3.35 2.24 (a) Including impact of not as yet declared cumulative dividends.
Computations of Diluted Earnings Per Common Share	8. Earnings per common share, continued The computations of diluted earnings per common share follow: Three Months Ended March 31 2019 2018 (In thousands, except per share) Net income available to common equity $ 464,612 334,480 Less: Income attributable to unvested stock-based compensation awards (2,526 ) (1,731 ) Net income available to common shareholders $ 462,086 332,749 Adjusted weighted-average shares outstanding: Common and unvested stock-based compensation awards 138,637 149,470 Less: Unvested stock-based compensation awards (748 ) (782 ) Plus: Incremental shares from assumed conversion of stock-based compensation awards and warrants to purchase common stock 31 217 Adjusted weighted-average shares outstanding 137,920 148,905 Diluted earnings per common share $ 3.35 2.23

Comprehensive income (Tables)

Comprehensive income (Tables)	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Components of Other Comprehensive Income (Loss) and Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income	The following tables display the components of other comprehensive income (loss) and amounts reclassified from accumulated other comprehensive income (loss) to net income: Investment Defined Benefit Total Amount Income Securities Plans Other Before Tax Tax Net (In thousands) Balance — January 1, 2019 $ (200,107 ) (354,502 ) (14,719 ) $ (569,328 ) 149,247 $ (420,081 ) Other comprehensive income before reclassifications: Unrealized holding gains, net 113,805 — — 113,805 (29,902 ) 83,903 Foreign currency translation adjustment — — 348 348 (73 ) 275 Unrealized gains on cash flow hedges — — 54,347 54,347 (14,288 ) 40,059 Total other comprehensive income before reclassifications 113,805 — 54,695 168,500 (44,263 ) 124,237 Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: Amortization of unrealized holding losses on held-to-maturity (“HTM”) securities 928 — — 928 (a) (245 ) 683 Losses realized in net income 7 — — 7 (b) (2 ) 5 Accretion of net gain on terminated cash flow hedges — — (28 ) (28 ) (c) 7 (21 ) Net yield adjustment from cash flow hedges currently in effect — — 6,625 6,625 (a) (1,742 ) 4,883 Amortization of prior service credit — (1,050 ) — (1,050 ) (d) 276 (774 ) Amortization of actuarial losses — 4,150 — 4,150 (d) (1,091 ) 3,059 Total other comprehensive income 114,740 3,100 61,292 179,132 (47,060 ) 132,072 Balance — March 31, 2019 $ (85,367 ) (351,402 ) 46,573 $ (390,196 ) 102,187 $ (288,009 ) Balance — January 1, 2018 $ (59,957 ) (413,168 ) (20,165 ) $ (493,290 ) 129,476 $ (363,814 ) Cumulative effect of change in accounting principle — equity securities (22,795 ) — — (22,795 ) 5,942 (16,853 ) Other comprehensive income before reclassifications: Unrealized holding losses, net (145,457 ) — — (145,457 ) 44,176 (101,281 ) Foreign currency translation adjustment — — 1,632 1,632 (342 ) 1,290 Unrealized losses on cash flow hedges — — (14,719 ) (14,719 ) 3,870 (10,849 ) Total other comprehensive income (loss) before reclassifications (145,457 ) — (13,087 ) (158,544 ) 47,704 (110,840 ) Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: Amortization of unrealized holding losses on HTM securities 810 — — 810 (a) (213 ) 597 Accretion of net gain on terminated cash flow hedges — — (28 ) (28 ) (c) 7 (21 ) Net yield adjustment from cash flow hedges currently in effect — — 580 580 (a) (152 ) 428 Amortization of prior service credit — (1,050 ) — (1,050 ) (d) 276 (774 ) Amortization of actuarial losses — 10,900 — 10,900 (d) (2,866 ) 8,034 Total other comprehensive income (loss) (144,647 ) 9,850 (12,535 ) (147,332 ) 44,756 (102,576 ) Balance — March 31, 2018 $ (227,399 ) (403,318 ) (32,700 ) $ (663,417 ) 180,174 $ (483,243 ) (a) Included in interest income. (b) Included in gain (loss) on bank investment securities. (c) Included in interest expense. (d) Included in other costs of operations.
Accumulated Other Comprehensive Income (Loss), Net	Accumulated other comprehensive income (loss), net consisted of the following: Investment Defined Benefit Securities Plans Other Total (In thousands) Balance — December 31, 2018 $ (147,526 ) (261,303 ) (11,252 ) $ (420,081 ) Net gain during period 84,591 2,285 45,196 132,072 Balance — March 31, 2019 $ (62,935 ) (259,018 ) 33,944 $ (288,009 )

Derivative financial instrume_2

Derivative financial instruments (Tables)	3 Months Ended
	Mar. 31, 2019
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Information about Interest Rate Swap Agreements	Information about interest rate swap agreements entered into for interest rate risk management purposes summarized by type of financial instrument the swap agreements were intended to hedge follows: Weighted- Average Rate Notional Average Estimated Fair Value Amount Maturity Fixed Variable Gain (Loss) (a) (In thousands) (In years) (In March 31, 2019 Fair value hedges: Fixed rate long-term borrowings (b) $ 4,450,000 2.6 2.47 % 3.04 % $ (4,390 ) Cash flow hedges: Interest payments on variable rate commercial real estate loans (b)(c) 29,750,000 1.4 2.29 % 2.49 % (12,534 ) Total $ 34,200,000 1.6 $ (16,924 ) December 31, 2018 Fair value hedges: Fixed rate long-term borrowings (b) $ 4,450,000 2.8 2.47 % 3.02 % $ 4,219 Cash flow hedges: Interest payments on variable rate commercial real estate loans (b)(d) 15,400,000 1.3 1.52 % 2.35 % 1,311 Total $ 19,850,000 1.7 $ 5,530 (a) Certain clearinghouse exchanges consider payments by counterparties for variation margin on derivative instruments to be settlements of those positions. The impact of such treatment at March 31, 2019 and December 31, 2018 was a reduction of the estimated fair value losses on interest rate swap agreements designated as fair value hedges of $11.9 million and $54.7 million, respectively, and on interest rate swap agreements designated as cash flow hedges of $65.7 million and $9.1 million, respectively. (b) Under the terms of these agreements, the Company receives settlement amounts at a fixed rate and pays at a variable rate. (c) (d) .
Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet	10. Derivative financial instruments, continued Information about the fair values of derivative instruments in the Company’s consolidated balance sheet and consolidated statement of income follows: Asset Derivatives Liability Derivatives Fair Value Fair Value March 31, December 31, March 31, December 31, 2019 2018 2019 2018 (In thousands) Derivatives designated and qualifying as hedging instruments Interest rate swap agreements (a) $ 267 $ 5,530 $ 17,191 $ — Commitments to sell real estate loans (a) 1,145 1,090 3,413 6,434 1,412 6,620 20,604 6,434 Derivatives not designated and qualifying as hedging instruments Mortgage-related commitments to originate real estate loans for sale (a) 8,059 9,304 626 1,592 Commitments to sell real estate loans (a) 3,687 3,702 2,843 4,535 Trading: Interest rate contracts (b) 199,404 118,687 92,383 169,255 Foreign exchange and other option and futures contracts (b) 7,880 10,549 6,390 8,870 219,030 142,242 102,242 184,252 Total derivatives $ 220,442 $ 148,862 $ 122,846 $ 190,686 (a) Asset derivatives are reported in other assets and liability derivatives are reported in other liabilities. (b) Asset derivatives are reported in trading account assets and liability derivatives are reported in other liabilities. The impact of variation margin payments at March 31, 2019 and December 31, 2018 was a reduction of the estimated fair value of interest rate contracts in the trading account in an asset position of $88.1 million and $170.7 million, respectively, and in a liability position of $122.8 million and $49.7 million, respectively. Carrying Amount of the Hedged Item Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount of the Hedged Item March 31, 2019 December 31, 2018 March 31, 2019 December 31, 2018 (In thousands) Location in the Consolidated Balance Sheet of the Hedged Items in Fair Value Hedges Long-term debt $ 4,428,645 $ 4,394,109 $ (17,088 ) $ (51,102 )
Information about Fair Values of Derivative Instruments in Consolidated Statement of Income	Amount of Gain (Loss) Recognized Three Months Ended March 31, 2019 Three Months Ended March 31, 2018 Derivative Hedged Item Derivative Hedged Item (In thousands) Derivatives in fair value hedging relationships Interest rate swap agreements: Fixed rate long-term borrowings (a) $ 34,180 (34,014 ) $ (42,390 ) 42,370 Derivatives not designated as hedging instruments Trading: Interest rate contracts (b) $ 2,711 $ (1,605 ) Foreign exchange and other option and futures contracts (b) 1,613 2,631 Total $ 4,324 $ 1,026 (a) Reported as an adjustment to interest expense. (b) Reported as trading account and foreign exchange gains.

Fair value measurements (Tables

Fair value measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Estimated Fair Value on Recurring Basis	The following tables present assets and liabilities at March 31, 2019 and December 31, 2018 measured at estimated fair value on a recurring basis: Fair Value Measurements Level 1 (a) Level 2 (a) Level 3 (In thousands) March 31, 2019 Trading account assets $ 276,322 $ 46,521 $ 229,801 $ — Investment securities available for sale: U.S. Treasury and federal agencies 1,139,428 — 1,139,428 — Obligations of states and political subdivisions 1,181 — 1,181 — Mortgage-backed securities: Government issued or guaranteed 7,053,907 — 7,053,907 — Privately issued 16 — — 16 Other debt securities 131,052 — 131,052 — 8,325,584 — 8,325,568 16 Equity securities 76,586 43,301 33,285 — Real estate loans held for sale 344,350 — 344,350 — Other assets (b) 13,158 — 5,099 8,059 Total assets $ 9,036,000 $ 89,822 $ 8,938,103 $ 8,075 Trading account liabilities $ 98,771 $ — $ 98,771 $ — Other liabilities (b) 24,073 — 23,447 626 Total liabilities $ 122,844 $ — $ 122,218 $ 626 December 31, 2018 Trading account assets $ 185,584 $ 46,018 $ 139,566 $ — Investment securities available for sale: U.S. Treasury and federal agencies 1,336,931 — 1,336,931 — Obligations of states and political subdivisions 1,659 — 1,659 — Mortgage-backed securities: Government issued or guaranteed 7,216,991 — 7,216,991 — Privately issued 22 — — 22 Other debt securities 126,906 — 126,906 — 8,682,509 — 8,682,487 22 Equity securities 93,917 71,989 21,928 — Real estate loans held for sale 551,697 — 551,697 — Other assets (b) 19,626 — 10,322 9,304 Total assets $ 9,533,333 $ 118,007 $ 9,406,000 $ 9,326 Trading account liabilities $ 178,125 $ — $ 178,125 $ — Other liabilities (b) 12,561 — 10,969 1,592 Total liabilities $ 190,686 $ — $ 189,094 $ 1,592 (a) There were no significant transfers between Level 1 and Level 2 of the fair value hierarchy during the three months ended March 31, 2019 and the year ended December 31, 2018. (b) Comprised predominantly of interest rate swap agreements used for interest rate risk management (Level 2), commitments to sell real estate loans (Level 2) and commitments to originate real estate loans to be held for sale (Level 3).
Changes in Level 3 Assets and Liabilities Measured at Estimated Fair Value on Recurring Basis	The changes in Level 3 assets and liabilities measured at estimated fair value on a recurring basis during the three months ended March 31, 2019 and 2018 were as follows: Investment Securities Available for Sale Privately Issued Mortgage-Backed Other Assets 2019 (In thousands) Balance — January 1, 2019 $ 22 7,712 Total gains (losses) realized/unrealized: Included in earnings — 16,546 (b) Settlements (6 ) — Transfers out of Level 3 (a) — (16,825 ) (c) Balance — March 31, 2019 $ 16 7,433 Changes in unrealized gains included in earnings related to assets still held at March 31, 2019 $ — 8,525 (b) 2018 Balance — January 1, 2018 $ 28 8,303 Total gains (losses) realized/unrealized: Included in earnings — 8,130 (b) Settlements (1 ) — Transfers out of Level 3 (a) — (7,673 ) (c) Balance — March 31, 2018 $ 27 8,760 Changes in unrealized gains included in earnings related to assets still held at March 31, 2018 $ — 8,778 (b) (a) The Company’s policy for transfers between fair value levels is to recognize the transfer as of the actual date of the event or change in circumstances that caused the transfer. (b) Reported as mortgage banking revenues in the consolidated statement of income and includes the fair value of commitment issuances and expirations. (c) Transfers out of Level 3 consist of interest rate locks transferred to closed loans.
Quantitative Information Related to Significant Unobservable Inputs	The following tables present quantitative information about significant unobservable inputs used in the fair value measurements for certain Level 3 assets and liabilities at March 31, 2019 and December 31, 2018: Fair Value Valuation Technique Unobservable Inputs/Assumptions Range (Weighted- Average) (In March 31, 2019 Recurring fair value measurements Privately issued mortgage-backed securities $ 16 Two independent pricing quotes — — Net other assets (liabilities) (a) 7,433 Discounted cash flow Commitment expirations 0%-94% (17%) December 31, 2018 Recurring fair value measurements Privately issued mortgage-backed securities $ 22 Two independent pricing quotes — — Net other assets (liabilities) (a) 7,712 Discounted cash flow Commitment expirations 0%-95% (13%) (a) Other Level 3 assets (liabilities) consist of commitments to originate real estate loans.
Carrying Amounts and Estimated Fair Value for Financial Instrument Assets (Liabilities)	The carrying amounts and estimated fair value for financial instrument assets (liabilities) are presented in the following table: March 31, 2019 Carrying Amount Estimated Fair Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 1,267,260 1,267,260 1,194,318 72,942 — Interest-bearing deposits at banks 7,602,897 7,602,897 — 7,602,897 — Trading account assets 276,322 276,322 46,521 229,801 — Investment securities 12,536,840 12,521,737 43,301 12,378,816 99,620 Loans and leases: Commercial loans and leases 23,090,204 22,755,670 — — 22,755,670 Commercial real estate loans 34,690,930 34,424,612 — 166,019 34,258,593 Residential real estate loans 16,769,933 16,764,418 — 3,877,095 12,887,323 Consumer loans 14,088,816 14,018,581 — — 14,018,581 Allowance for credit losses (1,019,337 ) — — — — Loans and leases, net 87,620,546 87,963,281 — 4,043,114 83,920,167 Accrued interest receivable 374,084 374,084 — 374,084 — Financial liabilities: Noninterest-bearing deposits $ (29,966,753 ) (29,966,753 ) — (29,966,753 ) — Savings and interest-checking deposits (52,932,297 ) (52,932,297 ) — (52,932,297 ) — Time deposits (6,501,509 ) (6,598,274 ) — (6,598,274 ) — Deposits at Cayman Islands office (1,069,191 ) (1,069,191 ) — (1,069,191 ) — Short-term borrowings (3,602,566 ) (3,602,566 ) — (3,602,566 ) — Long-term borrowings (8,476,024 ) (8,511,141 ) — (8,511,141 ) — Accrued interest payable (80,322 ) (80,322 ) — (80,322 ) — Trading account liabilities (98,771 ) (98,771 ) — (98,771 ) — Other financial instruments: Commitments to originate real estate loans for sale $ 7,433 7,433 — — 7,433 Commitments to sell real estate loans (1,424 ) (1,424 ) — (1,424 ) — Other credit-related commitments (126,811 ) (126,811 ) — — (126,811 ) Interest rate swap agreements used for interest rate risk management (16,924 ) (16,924 ) — (16,924 ) — December 31, 2018 Carrying Amount Estimated Fair Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 1,605,439 1,605,439 1,528,302 77,137 — Interest-bearing deposits at banks 8,105,197 8,105,197 — 8,105,197 — Trading account assets 185,584 185,584 46,018 139,566 — Investment securities 12,692,813 12,631,656 71,989 12,456,467 103,200 Loans and leases: Commercial loans and leases 22,977,976 22,587,387 — — 22,587,387 Commercial real estate loans 34,363,556 33,832,558 — 346,775 33,485,783 Residential real estate loans 17,154,446 16,974,545 — 3,920,447 13,054,098 Consumer loans 13,970,499 13,819,545 — — 13,819,545 Allowance for credit losses (1,019,444 ) — — — — Loans and leases, net 87,447,033 87,214,035 — 4,267,222 82,946,813 Accrued interest receivable 353,965 353,965 — 353,965 — Financial liabilities: Noninterest-bearing deposits $ (32,256,668 ) (32,256,668 ) — (32,256,668 ) — Savings and interest-checking deposits (50,963,744 ) (50,963,744 ) — (50,963,744 ) — Time deposits (6,124,254 ) (6,201,957 ) — (6,201,957 ) — Deposits at Cayman Islands office (811,906 ) (811,906 ) — (811,906 ) — Short-term borrowings (4,398,378 ) (4,398,378 ) — (4,398,378 ) — Long-term borrowings (8,444,914 ) (8,385,289 ) — (8,385,289 ) — Accrued interest payable (95,274 ) (95,274 ) — (95,274 ) — Trading account liabilities (178,125 ) (178,125 ) — (178,125 ) — Other financial instruments: Commitments to originate real estate loans for sale $ 7,712 7,712 — — 7,712 Commitments to sell real estate loans (6,177 ) (6,177 ) — (6,177 ) — Other credit-related commitments (131,688 ) (131,688 ) — — (131,688 ) Interest rate swap agreements used for interest rate risk management 5,530 5,530 — 5,530 —

Commitments and contingencies (

Commitments and contingencies (Tables)	3 Months Ended
	Mar. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Company's Significant Commitments	The following table presents the Company's significant commitments. Certain of these commitments are not included in the Company's consolidated balance sheet. March 31, December 31, 2019 2018 (In thousands) Commitments to extend credit Home equity lines of credit $ 5,529,111 5,484,197 Commercial real estate loans to be sold 199,722 229,401 Other commercial real estate 7,331,360 7,556,722 Residential real estate loans to be sold 314,402 245,211 Other residential real estate 277,708 219,351 Commercial and other 14,900,142 14,363,803 Standby letters of credit 2,246,864 2,326,991 Commercial letters of credit 59,464 55,808 Financial guarantees and indemnification contracts 3,703,612 3,529,136 Commitments to sell real estate loans 746,307 940,692

Segment information (Tables)

Segment information (Tables)	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Information about Company's Segments	Information about the Company's segments is presented in the following table: Three Months Ended March 31 2019 2018 Total Revenues(a) Inter- segment Revenues Net Income (Loss) Total Revenues(a) Inter- segment Revenues Net Income (Loss) (In thousands) Business Banking $ 139,322 856 43,271 $ 127,884 918 37,718 Commercial Banking 267,490 840 132,218 266,396 850 125,465 Commercial Real Estate 219,173 354 117,498 202,607 340 108,303 Discretionary Portfolio 63,917 (9,299 ) 39,172 50,038 (10,832 ) 19,739 Residential 83,761 14,514 12,941 82,458 15,421 14,946 Retail Banking 430,891 2,511 145,066 393,476 2,865 123,380 All Other 346,271 (9,776 ) (7,424 ) 311,354 (9,562 ) (76,941 ) Total $ 1,550,825 — 482,742 $ 1,434,213 — 352,610 Average Total Assets Three Months Ended March 31 Year Ended December 31 2019 2018 2018 (In millions) Business Banking $ 5,702 5,681 5,631 Commercial Banking 27,858 26,482 26,626 Commercial Real Estate 23,572 22,811 22,885 Discretionary Portfolio 30,341 34,095 32,123 Residential Mortgage Banking 2,071 2,278 2,161 Retail Banking 14,403 13,377 13,656 All Other 12,892 12,960 13,877 Total $ 116,839 117,684 116,959 (a) Total revenues are comprised of net interest income and other income. Net interest income is the difference between taxable-equivalent interest earned on assets and interest paid on liabilities owed by a segment and a funding charge (credit) based on the Company's internal funds transfer and allocation methodology. Segments are charged a cost to fund any assets (e.g. loans) and are paid a funding credit for any funds provided (e.g. deposits). The taxable-equivalent adjustment aggregated $5,967,000 and $4,809,000 for the three-month periods ended March 31, 2019 and 2018, respectively, and is eliminated in "All Other" total revenues. Intersegment revenues are included in total revenues of the reportable segments. The elimination of intersegment revenues is included in the determination of "All Other" total revenues

Investment Securities - Additio

Investment Securities - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2019USD ($)Security	Mar. 31, 2018USD ($)
Investment Holdings [Line Items]
Gross realized gains(loss) on sale of investment securities	$ 0	$ 0
Gain (loss) on bank investment securities	$ 11,841,000	$ (9,431,000)
Number of debt securities with aggregate gross unrealized losses | Security	1,166
Unrealized losses on individual debt securities	$ (145,000,000)
Cost method equity securities	420,000,000
Retained Earnings [Member] | Adjustments for New Accounting Pronouncement [Member]
Investment Holdings [Line Items]
Reclassification from accumulated comprehensive income to retained earnings, net of tax	$ 17,000,000

Investment Securities - Amortiz

Investment Securities - Amortized Cost and Estimated Fair Value of Investment Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Schedule Of Amortized Cost And Estimated Fair Value Of Investment Securities [Line Items]
Investment securities available for sale, amortized cost	$ 8,398,686	$ 8,869,423
Investment securities available for sale, gross unrealized gains	31,216	16,528
Investment securities available for sale, gross unrealized losses	104,318	203,442
Investment securities available for sale, estimated fair value	8,325,584	8,682,509
Amortized cost for held to maturity	3,714,699	3,316,640
Gross unrealized gains for held to maturity	25,444	16,532
Gross unrealized losses for held to maturity	40,547	77,689
Estimated fair value for held to maturity	3,699,596	3,255,483
Equity and other securities, Amortized Cost	468,232	677,187
Equity securities, Gross Unrealized Gains	28,913	17,295
Equity securities, Gross Unrealized Losses	588	818
Equity and other securities, Estimated Fair Value	496,557	693,664
Other securities, Amortized cost	419,971	599,747
Other securities, Estimated fair value	419,971	599,747
Total debt securities Amortized cost	12,113,385	12,186,063
Total debt securities Gross unrealized gains	56,660	33,060
Total debt securities Gross unrealized losses	144,865	281,131
Total debt securities Estimated fair value	12,025,180	11,937,992
Readily marketable securities Amortized cost	48,261	77,440
Readily marketable securities Gross unrealized gains	28,913	17,295
Readily marketable securities Gross unrealized losses	588	818
Readily marketable securities Estimated fair value	76,586	93,917
U.S. Treasury and Federal Agencies [Member]
Schedule Of Amortized Cost And Estimated Fair Value Of Investment Securities [Line Items]
Investment securities available for sale, amortized cost	1,144,288	1,346,782
Investment securities available for sale, gross unrealized gains	4
Investment securities available for sale, gross unrealized losses	4,864	9,851
Investment securities available for sale, estimated fair value	1,139,428	1,336,931
Amortized cost for held to maturity	944,230	446,542
Gross unrealized gains for held to maturity	735
Gross unrealized losses for held to maturity	15	239
Estimated fair value for held to maturity	944,950	446,303
Obligations of States and Political Subdivisions [Member]
Schedule Of Amortized Cost And Estimated Fair Value Of Investment Securities [Line Items]
Investment securities available for sale, amortized cost	1,181	1,660
Investment securities available for sale, gross unrealized gains	4	4
Investment securities available for sale, gross unrealized losses	4	5
Investment securities available for sale, estimated fair value	1,181	1,659
Amortized cost for held to maturity	6,810	7,494
Gross unrealized gains for held to maturity	27	22
Gross unrealized losses for held to maturity		12
Estimated fair value for held to maturity	6,837	7,504
Government Issued or Guaranteed [Member]
Schedule Of Amortized Cost And Estimated Fair Value Of Investment Securities [Line Items]
Investment securities available for sale, amortized cost	7,115,459	7,383,340
Investment securities available for sale, gross unrealized gains	29,959	15,754
Investment securities available for sale, gross unrealized losses	91,511	182,103
Investment securities available for sale, estimated fair value	7,053,907	7,216,991
Amortized cost for held to maturity	2,652,219	2,745,776
Gross unrealized gains for held to maturity	11,876	4,165
Gross unrealized losses for held to maturity	19,472	55,111
Estimated fair value for held to maturity	2,644,623	2,694,830
Privately Issued [Member]
Schedule Of Amortized Cost And Estimated Fair Value Of Investment Securities [Line Items]
Investment securities available for sale, amortized cost	16	24
Investment securities available for sale, gross unrealized losses		2
Investment securities available for sale, estimated fair value	16	22
Amortized cost for held to maturity	107,858	113,160
Gross unrealized gains for held to maturity	12,806	12,345
Gross unrealized losses for held to maturity	21,060	22,327
Estimated fair value for held to maturity	99,604	103,178
Other Debt Securities [Member]
Schedule Of Amortized Cost And Estimated Fair Value Of Investment Securities [Line Items]
Investment securities available for sale, amortized cost	137,742	137,617
Investment securities available for sale, gross unrealized gains	1,249	770
Investment securities available for sale, gross unrealized losses	7,939	11,481
Investment securities available for sale, estimated fair value	131,052	126,906
Amortized cost for held to maturity	3,582	3,668
Estimated fair value for held to maturity	$ 3,582	$ 3,668

Investment Securities - Amort_2

Investment Securities - Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt securities available for sale:
Due in one year or less	$ 1,141,640
Due after one year through five years	9,470
Due after five years through ten years	102,101
Due after ten years	30,000
Total available for sale (amortized cost)	1,283,211
Mortgage-backed securities available for sale	7,115,475
Investment securities available for sale, amortized cost	8,398,686	$ 8,869,423
Debt securities held to maturity:
Due in one year or less	947,176
Due after one year through five years	3,864
Due after ten years	3,582
Total available for held to maturity (amortized cost)	954,622
Mortgage-backed securities held to maturity	2,760,077
Amortized cost for held to maturity	3,714,699	3,316,640
Debt securities available for sale:
Due in one year or less	1,136,864
Due after one year through five years	9,355
Due after five years through ten years	99,642
Due after ten years	25,800
Total available for sale (fair value)	1,271,661
Mortgage-backed securities available for sale	7,053,923
Total	8,325,584	8,682,509
Debt securities held to maturity:
Due in one year or less	947,905
Due after one year through five years	3,882
Due after ten years	3,582
Total available for held to maturity (fair value)	955,369
Mortgage-backed securities held to maturity	2,744,227
Total	$ 3,699,596	$ 3,255,483

Investment Securities - Investm

Investment Securities - Investment Securities in Continuous Unrealized Loss Position (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Estimated fair value, Less than 12 months	$ 55,221	$ 459,960
Available For Sale Securities Continuous Unrealized Losses Position Less Than Twelve Months Aggregate Losses	(406)	(5,088)
Estimated fair value, 12 months or more	6,282,481	7,048,346
Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or More Aggregate Losses	(103,912)	(198,354)
Held to maturity, Estimated fair value, Less than 12 months	249,082	625,657
Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses	(15)	(1,228)
Held to maturity, Estimated fair value, 12 months or more	1,671,671	2,137,792
Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Aggregate Losses	(40,532)	(76,461)
Total investment securities, fair value less than 12 months	304,303	1,085,617
Investment Securities Continuous Unrealized Loss Position Less Than Twelve Months Aggregate Losses	(421)	(6,316)
Total of investment securities, fair value, 12 Months or More	7,954,152	9,186,138
Investment Securities Continuous Unrealized Loss Position Twelve Months or Longer Aggregate Losses	(144,444)	(274,815)
U.S. Treasury and Federal Agencies [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Estimated fair value, Less than 12 months	274	273
Available For Sale Securities Continuous Unrealized Losses Position Less Than Twelve Months Aggregate Losses	(1)	(2)
Estimated fair value, 12 months or more	1,137,550	1,335,559
Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or More Aggregate Losses	(4,863)	(9,849)
Held to maturity, Estimated fair value, Less than 12 months	249,082	446,303
Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses	(15)	(239)
Obligations of States and Political Subdivisions [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Estimated fair value, Less than 12 months		629
Available For Sale Securities Continuous Unrealized Losses Position Less Than Twelve Months Aggregate Losses		(5)
Estimated fair value, 12 months or more	507
Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or More Aggregate Losses	(4)
Held to maturity, Estimated fair value, 12 months or more		3,126
Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Aggregate Losses		(12)
Government Issued or Guaranteed [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Estimated fair value, Less than 12 months	18,447	405,558
Available For Sale Securities Continuous Unrealized Losses Position Less Than Twelve Months Aggregate Losses	(111)	(2,892)
Estimated fair value, 12 months or more	5,076,762	5,646,773
Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or More Aggregate Losses	(91,400)	(179,211)
Held to maturity, Estimated fair value, Less than 12 months		179,354
Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses		(989)
Held to maturity, Estimated fair value, 12 months or more	1,620,580	2,082,723
Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Aggregate Losses	(19,472)	(54,122)
Other Debt Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Estimated fair value, Less than 12 months	36,500	53,478
Available For Sale Securities Continuous Unrealized Losses Position Less Than Twelve Months Aggregate Losses	(294)	(2,187)
Estimated fair value, 12 months or more	67,662	66,014
Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or More Aggregate Losses	(7,645)	(9,294)
Privately Issued [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Estimated fair value, Less than 12 months		22
Available For Sale Securities Continuous Unrealized Losses Position Less Than Twelve Months Aggregate Losses		(2)
Held to maturity, Estimated fair value, 12 months or more	51,091	51,943
Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Aggregate Losses	$ (21,060)	$ (22,327)

Loans and Leases and the Allo_3

Loans and Leases and the Allowance for Credit Losses - Summary of Current, Past Due and Nonaccrual Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	$ 86,248,711	$ 86,140,950
30-89 Days Past Due	942,526	866,337
Accruing Loans Past Due 90 Days or More	244,257	222,527
Purchased Impaired	278,783	303,305
Nonaccrual	881,611	893,608
Loans and leases, net of unearned discount	88,639,883	88,466,477
Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	43,995	39,750
Commercial, Financial, Leasing, etc. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	22,701,500	22,701,020
30-89 Days Past Due	141,555	39,798
Accruing Loans Past Due 90 Days or More	1,047	2,567
Nonaccrual	245,819	234,423
Loans and leases, net of unearned discount	23,090,204	22,977,976
Commercial, Financial, Leasing, etc. [Member] | Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	283	168
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	25,441,419	25,250,983
30-89 Days Past Due	159,209	134,474
Accruing Loans Past Due 90 Days or More	7,394	11,457
Purchased Impaired	10,305	9,769
Nonaccrual	207,709	203,672
Loans and leases, net of unearned discount	25,826,194	25,610,365
Commercial [Member] | Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	158	10
Residential Builder and Developer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	1,738,846	1,665,178
30-89 Days Past Due	2,190	20,333
Purchased Impaired	549
Nonaccrual	4,392	4,798
Loans and leases, net of unearned discount	1,745,977	1,690,309
Other Commercial Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	7,036,036	6,982,077
30-89 Days Past Due	31,152	43,615
Accruing Loans Past Due 90 Days or More	31,032	14,344
Purchased Impaired	640	641
Nonaccrual	19,899	22,205
Loans and leases, net of unearned discount	7,118,759	7,062,882
Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	13,337,558	13,591,790
30-89 Days Past Due	406,106	404,808
Accruing Loans Past Due 90 Days or More	199,940	189,682
Purchased Impaired	187,631	203,044
Nonaccrual	210,266	233,352
Loans and leases, net of unearned discount	14,347,926	14,629,326
Residential [Member] | Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	6,425	6,650
Residential Limited Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	2,186,132	2,278,040
30-89 Days Past Due	71,354	72,544
Purchased Impaired	79,658	89,851
Nonaccrual	84,863	84,685
Loans and leases, net of unearned discount	2,422,007	2,525,120
Home Equity Lines and Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	4,634,634	4,758,513
30-89 Days Past Due	31,145	25,416
Nonaccrual	69,245	71,292
Loans and leases, net of unearned discount	4,739,895	4,860,254
Home Equity Lines and Loans [Member] | Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	4,871	5,033
Recreational Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	4,295,732	4,085,781
30-89 Days Past Due	22,549	29,947
Nonaccrual	10,972	11,199
Loans and leases, net of unearned discount	4,329,488	4,127,162
Recreational Finance [Member] | Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	235	235
Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	3,619,015	3,555,757
30-89 Days Past Due	62,846	79,804
Nonaccrual	21,209	23,359
Loans and leases, net of unearned discount	3,703,070	3,658,920
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	1,257,839	1,271,811
30-89 Days Past Due	14,420	15,598
Accruing Loans Past Due 90 Days or More	4,844	4,477
Nonaccrual	7,237	4,623
Loans and leases, net of unearned discount	1,316,363	1,324,163
Other [Member] | Accruing Loans Acquired at Discount [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing Loans Past Due 90 Days or More	$ 32,023	$ 27,654

Loans and Leases and the Allo_4

Loans and Leases and the Allowance for Credit Losses - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Loans And Leases Receivable [Line Items]
Commercial real estate loans held for sale	$ 166	$ 347
Contractual principal and interest payments	$ 279	303
Minimum delinquency period for loan level collectability analysis consumer mortgage	150 days
Amount of foreclosed residential real estate property held	$ 81	77
Loans secured by residential real estate that were in the process of foreclosure	$ 382	391
Percentage loans in the process of foreclosure, serviced by other entities, classified as purchased impaired	38.00%
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed	21.00%
Guaranteed amount included in the estimated residual value of leased assets associated with direct financing leases	$ 35	$ 39
Maximum [Member]
Loans And Leases Receivable [Line Items]
Purchased impaired loans as a percentage of total assets	1.00%	1.00%
Minimum [Member]
Loans And Leases Receivable [Line Items]
Loan delinquent period	90 days
Residential Mortgage Loans [Member]
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	$ 178	$ 205
Carrying value of loans for which partial charge-off has been recognized	29	29
Mortgage loans on real real estate not requiring charge off due to collateral carrying amount	19	21
Home Equity Loans and Lines of Credit [Member]
Loans And Leases Receivable [Line Items]
Carrying value of loans for which partial charge-off has been recognized	22	23
Mortgage loans on real real estate not requiring charge off due to collateral carrying amount	$ 33	$ 31

Loans and Leases and the Allo_5

Loans and Leases and the Allowance for Credit Losses - Outstanding Principal Balance and Carrying Amount of Loans and Included in Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Outstanding principal and carrying value of acquired loans recorded at fair value
Outstanding principal balance	$ 960,990	$ 1,016,785
Carrying amount	686,116	727,491
Commercial, Financial, Leasing, etc. [Member]
Outstanding principal and carrying value of acquired loans recorded at fair value
Carrying amount	25,060	27,073
Commercial Real Estate [Member]
Outstanding principal and carrying value of acquired loans recorded at fair value
Carrying amount	125,310	135,047
Residential Real Estate [Member]
Outstanding principal and carrying value of acquired loans recorded at fair value
Carrying amount	442,260	473,511
Consumer [Member]
Outstanding principal and carrying value of acquired loans recorded at fair value
Carrying amount	$ 93,486	$ 91,860

Loans and Leases and the Allo_6

Loans and Leases and the Allowance for Credit Losses - Summary of Changes in Accretable Yield for Acquired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Purchased Impaired [Member]
Summary of changes in Accretable Yield for acquired loans
Balance at beginning of period	$ 147,210	$ 157,918
Interest income	(18,082)	(9,819)
Reclassifications from nonaccretable balance	11,189	908
Balance at end of period	140,317	149,007
Other Acquired [Member]
Summary of changes in Accretable Yield for acquired loans
Balance at beginning of period	96,907	133,162
Interest income	(9,717)	(15,112)
Reclassifications from nonaccretable balance	4,865	207
Other	1,632	(73)
Balance at end of period	$ 93,687	$ 118,184

Loans and Leases and the Allo_7

Loans and Leases and the Allowance for Credit Losses - Changes in Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 1,019,444	$ 1,017,198
Provision for credit losses	22,000	43,000
Net charge-offs
Charge-offs	(45,100)	(56,752)
Recoveries	22,993	16,225
Net (charge-offs) recoveries	(22,107)	(40,527)
Ending balance	1,019,337	1,019,671
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	330,055	328,599
Provision for credit losses	6,271	7,230
Net charge-offs
Charge-offs	(8,500)	(14,581)
Recoveries	7,794	4,823
Net (charge-offs) recoveries	(706)	(9,758)
Ending balance	335,620	326,071
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	341,655	374,085
Provision for credit losses	(4,203)	(5,225)
Net charge-offs
Charge-offs	(283)	(1,366)
Recoveries	826	223
Net (charge-offs) recoveries	543	(1,143)
Ending balance	337,995	367,717
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	69,125	65,405
Provision for credit losses	(2,447)	10,486
Net charge-offs
Charge-offs	(3,372)	(4,354)
Recoveries	1,830	1,510
Net (charge-offs) recoveries	(1,542)	(2,844)
Ending balance	65,136	73,047
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	200,564	170,809
Provision for credit losses	22,883	29,814
Net charge-offs
Charge-offs	(32,945)	(36,451)
Recoveries	12,543	9,669
Net (charge-offs) recoveries	(20,402)	(26,782)
Ending balance	203,045	173,841
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	78,045	78,300
Provision for credit losses	(504)	695
Net charge-offs
Ending balance	$ 77,541	$ 78,995

Loans and Leases and the Allo_8

Loans and Leases and the Allowance for Credit Losses - Impaired Loans and Leases (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	$ 575,585	$ 542,255
Unpaid principal balance with related allowance	663,177	630,609
Related allowance	81,991	79,646
Recorded investment with no related allowance	254,283	254,196
Unpaid principal balance with no related allowance	283,855	305,559
Recorded investment	829,868	796,451
Unpaid principal balance	947,032	936,168
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	102,247	110,253
Unpaid principal balance with related allowance	119,062	125,117
Related allowance	10,449	11,937
Recorded investment with no related allowance	125,289	113,376
Unpaid principal balance with no related allowance	138,095	124,657
Recorded investment	227,536	223,629
Unpaid principal balance	257,157	249,774
Automobile [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	3,522	3,527
Unpaid principal balance with related allowance	3,603	3,599
Related allowance	729	729
Recorded investment	3,522	3,527
Unpaid principal balance	3,603	3,599
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	201,337	153,478
Unpaid principal balance with related allowance	220,116	175,549
Related allowance	50,192	46,034
Recorded investment with no related allowance	91,355	105,507
Unpaid principal balance with no related allowance	97,342	136,128
Recorded investment	292,692	258,985
Unpaid principal balance	317,458	311,677
Residential Builder and Developer [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	6,805	5,981
Unpaid principal balance with related allowance	7,399	6,557
Related allowance	327	462
Recorded investment with no related allowance	2,756	2,593
Unpaid principal balance with no related allowance	2,781	2,602
Recorded investment	9,561	8,574
Unpaid principal balance	10,180	9,159
Other Commercial Construction [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	10,696	10,563
Unpaid principal balance with related allowance	13,624	11,113
Related allowance	703	640
Recorded investment with no related allowance	9,203	11,710
Unpaid principal balance with no related allowance	9,432	11,880
Recorded investment	19,899	22,273
Unpaid principal balance	23,056	22,993
Residential [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	121,351	124,974
Unpaid principal balance with related allowance	142,872	147,817
Related allowance	5,291	5,402
Recorded investment with no related allowance	19,535	15,379
Unpaid principal balance with no related allowance	25,771	20,496
Recorded investment	140,886	140,353
Unpaid principal balance	168,643	168,313
Residential Limited Documentation [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	71,113	74,156
Unpaid principal balance with related allowance	86,276	90,066
Related allowance	3,000	3,000
Recorded investment with no related allowance	6,145	5,631
Unpaid principal balance with no related allowance	10,434	9,796
Recorded investment	77,258	79,787
Unpaid principal balance	96,710	99,862
Home Equity Lines and Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	47,363	47,982
Unpaid principal balance with related allowance	52,583	53,248
Related allowance	9,025	9,135
Recorded investment	47,363	47,982
Unpaid principal balance	52,583	53,248
Recreational Finance [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	5,539	6,138
Unpaid principal balance with related allowance	5,740	9,163
Related allowance	1,147	1,261
Recorded investment	5,539	6,138
Unpaid principal balance	5,740	9,163
Other [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance	5,612	5,203
Unpaid principal balance with related allowance	11,902	8,380
Related allowance	1,128	1,046
Recorded investment	5,612	5,203
Unpaid principal balance	$ 11,902	$ 8,380

Loans and Leases and the Allo_9

Loans and Leases and the Allowance for Credit Losses - Interest Income Recognized on Impaired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	$ 800,863	$ 745,805
Interest income recognized, Total	8,917	9,971
Interest income recognized, Cash basis	5,771	7,320
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	225,374	181,846
Interest income recognized, Total	1,091	3,147
Interest income recognized, Cash basis	1,091	3,147
Commercial, Financial, Leasing, etc. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	265,248	272,172
Interest income recognized, Total	3,038	783
Interest income recognized, Cash basis	3,038	783
Residential Builder and Developer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	8,875	9,840
Interest income recognized, Total	115	1,682
Interest income recognized, Cash basis	115	1,682
Other Commercial Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	20,398	10,102
Interest income recognized, Total	564	6
Interest income recognized, Cash basis	564	6
Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	140,403	121,209
Interest income recognized, Total	2,022	1,902
Interest income recognized, Cash basis	666	902
Residential Limited Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	78,238	85,595
Interest income recognized, Total	1,353	1,728
Interest income recognized, Cash basis	208	696
Home Equity Lines and Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	47,556	48,797
Interest income recognized, Total	416	414
Interest income recognized, Cash basis	62	86
Recreational Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	6,023	1,458
Interest income recognized, Total	142	63
Interest income recognized, Cash basis	4	2
Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	3,530	13,125
Interest income recognized, Total	54	224
Interest income recognized, Cash basis	19	15
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment	5,218	1,661
Interest income recognized, Total	122	22
Interest income recognized, Cash basis	$ 4	$ 1

Loans and Leases and the All_10

Loans and Leases and the Allowance for Credit Losses - Summary of Loan Grades (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	$ 88,639,883	$ 88,466,477
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	23,090,204	22,977,976
Commercial, Financial, Leasing, etc. [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	21,734,455	21,693,705
Commercial, Financial, Leasing, etc. [Member] | Criticized Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	1,109,930	1,049,848
Commercial, Financial, Leasing, etc. [Member] | Criticized Nonaccrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	245,819	234,423
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	25,826,194	25,610,365
Commercial [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	24,686,100	24,539,706
Commercial [Member] | Criticized Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	932,385	866,987
Commercial [Member] | Criticized Nonaccrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	207,709	203,672
Residential Builder and Developer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	1,745,977	1,690,309
Residential Builder and Developer [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	1,535,068	1,546,002
Residential Builder and Developer [Member] | Criticized Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	206,517	139,509
Residential Builder and Developer [Member] | Criticized Nonaccrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	4,392	4,798
Other Commercial Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	7,118,759	7,062,882
Other Commercial Construction [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	6,870,882	6,890,562
Other Commercial Construction [Member] | Criticized Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	227,978	150,115
Other Commercial Construction [Member] | Criticized Nonaccrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	$ 19,899	$ 22,205

Loans and Leases and the All_11

Loans and Leases and the Allowance for Credit Losses - Allocation of Allowance for Credit Losses on Basis of Company's Impairment Methodology (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	$ 81,991	$ 79,646
Allowance for credit losses	849,988	849,356
Allowance for credit losses	1,019,337	1,019,444	$ 1,019,671	$ 1,017,198
Purchased Impaired [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	9,817	12,397
Allocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	941,796	941,399
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	77,541	78,045	$ 78,995	$ 78,300
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	50,192	46,034
Allowance for credit losses	285,428	284,021
Commercial, Financial, Leasing, etc. [Member] | Allocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	335,620	330,055
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	11,479	13,039
Allowance for credit losses	326,516	328,616
Commercial Real Estate [Member] | Allocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	337,995	341,655
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	8,291	8,402
Allowance for credit losses	47,028	48,326
Residential Real Estate [Member] | Purchased Impaired [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	9,817	12,397
Residential Real Estate [Member] | Allocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	65,136	69,125
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	12,029	12,171
Allowance for credit losses	191,016	188,393
Consumer Loans [Member] | Allocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses	$ 203,045	$ 200,564

Loans and Leases and the All_12

Loans and Leases and the Allowance for Credit Losses - Recorded Investment in Loans and Leases on Basis of Company's Impairment Methodology (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	$ 88,639,883	$ 88,466,477
Individually Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	829,868	796,451
Collectively Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	87,531,232	87,366,721
Purchased Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	278,783	303,305
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	23,090,204	22,977,976
Commercial, Financial, Leasing, etc. [Member] | Individually Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	292,692	258,985
Commercial, Financial, Leasing, etc. [Member] | Collectively Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	22,797,512	22,718,991
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	34,690,930	34,363,556
Commercial Real Estate [Member] | Individually Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	256,996	254,476
Commercial Real Estate [Member] | Collectively Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	34,422,440	34,098,670
Commercial Real Estate [Member] | Purchased Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	11,494	10,410
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	16,769,933	17,154,446
Residential Real Estate [Member] | Individually Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	218,144	220,140
Residential Real Estate [Member] | Collectively Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	16,284,500	16,641,411
Residential Real Estate [Member] | Purchased Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	267,289	292,895
Consumer Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	14,088,816	13,970,499
Consumer Loans [Member] | Individually Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	62,036	62,850
Consumer Loans [Member] | Collectively Evaluated for Impairment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and leases, net of unearned discount	$ 14,026,780	$ 13,907,649

Loans and Leases and the All_13

Loans and Leases and the Allowance for Credit Losses - Loan Modification Activities that were Considered Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)Modification	Mar. 31, 2018USD ($)Modification
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	132	150
Pre-modification Recorded Investment	$ 46,537	$ 70,002
Post- modification	$ 46,291	$ 72,622
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	15	20
Pre-modification Recorded Investment	$ 9,241	$ 6,780
Post- modification	8,954	6,751
Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	10,924	49,656
Principal Deferral [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	987	5,824
Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Post- modification		624
Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	35,367	22,342
Combination of Concession Types [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 7,967	$ 927
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	65	56
Pre-modification Recorded Investment	$ 30,615	$ 47,994
Post- modification	30,744	49,344
Commercial, Financial, Leasing, etc. [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	6,474	35,673
Commercial, Financial, Leasing, etc. [Member] | Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Post- modification		624
Commercial, Financial, Leasing, etc. [Member] | Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 24,270	$ 13,047
Residential Builder and Developer [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	2
Pre-modification Recorded Investment	$ 1,330
Post- modification	1,068
Residential Builder and Developer [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 1,068
Other Commercial Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	1	1
Pre-modification Recorded Investment	$ 418	$ 752
Post- modification	366	746
Other Commercial Construction [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification		$ 746
Other Commercial Construction [Member] | Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 366
Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	17	47
Pre-modification Recorded Investment	$ 3,816	$ 12,636
Post- modification	4,024	13,847
Residential [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	1,751	6,945
Residential [Member] | Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 2,273	$ 6,902
Residential Limited Documentation [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	1	2
Pre-modification Recorded Investment	$ 236	$ 295
Post- modification	239	385
Residential Limited Documentation [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 239	267
Residential Limited Documentation [Member] | Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification		$ 118
Home Equity Lines and Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	7	14
Pre-modification Recorded Investment	$ 476	$ 1,348
Post- modification	491	1,352
Home Equity Lines and Loans [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	37	4
Home Equity Lines and Loans [Member] | Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 454	$ 1,348
Automobile [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	20	8
Pre-modification Recorded Investment	$ 317	$ 148
Post- modification	317	148
Automobile [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	280	$ 148
Automobile [Member] | Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 37
Recreational Finance [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	4	2
Pre-modification Recorded Investment	$ 88	$ 49
Post- modification	88	49
Recreational Finance [Member] | Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Post- modification	$ 88	$ 49

Loans and Leases and the All_14

Loans and Leases and the Allowance for Credit Losses - Summary of Lease Financing Receivables (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Direct financings:
Lease payments receivable	$ 1,140,794	$ 1,155,464
Estimated residual value of leased assets	82,686	85,169
Unearned income	(106,797)	(110,458)
Investment in direct financings	1,116,683	1,130,175
Leveraged leases:
Lease payments receivable	82,841	85,007
Estimated residual value of leased assets	81,261	81,261
Unearned income	(33,273)	(33,717)
Investment in leveraged leases	130,829	132,551
Total investment in leases	1,247,512	1,262,726
Deferred taxes payable arising from leveraged leases	$ 73,808	$ 74,995

Loans and Leases and the All_15

Loans and Leases and the Allowance for Credit Losses - Minimum Future Lease Payments to be Received from Lease Financings (Detail) $ in Thousands	Mar. 31, 2019USD ($)
Receivables [Abstract]
2020	$ 322,403
2021	302,912
2022	220,516
2023	148,313
2024	84,610
Later years	144,881
Total	$ 1,223,635

Operating Leases - Summary of R

Operating Leases - Summary of Right-of-Use Assets Recognized as Component of Premises and Equipment and Lease Liabilities Recognized as Component of Accrued Interest and Other Liabilities in Consolidated Balance Sheet (Detail) $ in Thousands	Mar. 31, 2019USD ($)
Lessee Disclosure [Abstract]
Right-of-use assets	$ 392,847
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentNet
Lease liabilities	$ 419,958
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilities

Operating Leases - Additional I

Operating Leases - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Period of noncancelable operating lease in years	23 years

Operating Leases - Summary of L

Operating Leases - Summary of Lease Costs for Operating Leases, Cash Paid Toward Lease Liabilities, and Weighted-Average Remaining Term and Discount Rates of Operating Leases (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)
Lease cost
Operating lease cost	$ 24,639
Short-term lease cost	34
Variable lease cost	466
Sublease income	(1,917)
Total net lease cost	23,222
Other information
Right-of-use assets obtained in exchange for new operating lease liabilities	20,410
Cash paid toward lease liabilities	$ 25,656
Weighted-average remaining lease term	7 years
Weighted-average discount rate	3.20%

Operating Leases - Summary of M

Operating Leases - Summary of Minimum Lease Payments Under Noncancelable Operating Leases (Detail) $ in Thousands	Mar. 31, 2019USD ($)
Leases [Abstract]
2020	$ 93,460
2021	87,025
2022	71,369
2023	58,847
2024	41,034
Later years	111,683
Total lease payments	463,418
Less: imputed interest	43,460
Lease liabilities	$ 419,958

Borrowings - Additional Informa

Borrowings - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Debt Instruments [Abstract]
Junior subordinated debentures	$ 523
Debt Maturity, Start Year	Jan. 1, 2027
Debt Maturity, End Year	Dec. 31, 2033
Agreements to repurchase securities	$ 406	$ 409
Collateral posted	$ 425	$ 428

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Additional Information (Detail1)	Mar. 31, 2019
Maximum [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-04-01
Disaggregation Of Revenue [Line Items]
Period of satisfaction of contract with customer	1 year

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Uncollected amounts receivable	$ 54	$ 56
Accrued interest and other liabilities [Member]
Disaggregation Of Revenue [Line Items]
Deferred revenue	$ 43	$ 43

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Summary of Sources of Noninterest Income that are Subject to Noted Accounting Guidance (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation Of Revenue [Line Items]
Brokerage services income	$ 12,476	$ 13,392
Other revenues from operations:
Total other income	500,765	458,696
Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	103,112	105,115
Trust Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	132,786	131,375
ASU 2014-09 [Member]
Disaggregation Of Revenue [Line Items]
Brokerage services income	12,476	13,392
Other revenues from operations:
Merchant discount and credit card fees	25,138	24,772
Other	23,237	22,890
Total other income	296,749	297,544
ASU 2014-09 [Member] | Business Banking [Member]
Other revenues from operations:
Merchant discount and credit card fees	8,882	7,503
Total other income	23,996	22,907
ASU 2014-09 [Member] | Commercial Banking [Member]
Other revenues from operations:
Merchant discount and credit card fees	12,092	12,712
Other	1,002	1,563
Total other income	36,518	38,929
ASU 2014-09 [Member] | Commercial Real Estate [Member]
Other revenues from operations:
Merchant discount and credit card fees	606	554
Other	1,788	859
Total other income	4,920	4,177
ASU 2014-09 [Member] | Discretionary Portfolio [Member]
Other revenues from operations:
Other	401	452
Total other income	401	452
ASU 2014-09 [Member] | Residential Mortgage Banking [Member]
Other revenues from operations:
Other	1,064	1,043
Total other income	1,066	1,046
ASU 2014-09 [Member] | Retail Banking [Member]
Other revenues from operations:
Merchant discount and credit card fees	3,138	3,388
Other	8,494	9,865
Total other income	72,783	73,854
ASU 2014-09 [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Brokerage services income	12,476	13,392
Other revenues from operations:
Merchant discount and credit card fees	420	615
Other	10,488	9,108
Total other income	157,065	156,179
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	103,112	105,115
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member] | Business Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	15,109	15,404
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member] | Commercial Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	23,210	24,654
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member] | Commercial Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	2,526	2,764
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member] | Residential Mortgage Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	2	3
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member] | Retail Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	61,151	60,601
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	1,114	1,689
ASU 2014-09 [Member] | Trust Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	132,786	131,375
ASU 2014-09 [Member] | Trust Income [Member] | Business Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	5
ASU 2014-09 [Member] | Trust Income [Member] | Commercial Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	214
ASU 2014-09 [Member] | Trust Income [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	$ 132,567	$ 131,375

Pension Plans and Other Postr_3

Pension Plans and Other Postretirement Benefits - Net Periodic Defined Benefit Cost for Defined Benefit Plans (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4,087	$ 5,103
Interest cost on projected benefit obligation	20,200	18,805
Expected return on plan assets	(30,600)	(30,875)
Amortization of prior service cost (credit)	125	125
Amortization of net actuarial loss (gain)	4,450	11,100
Net periodic cost (benefit)	(1,738)	4,258
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	200	226
Interest cost on projected benefit obligation	603	557
Amortization of prior service cost (credit)	(1,175)	(1,175)
Amortization of net actuarial loss (gain)	(300)	(200)
Net periodic cost (benefit)	$ (672)	$ (592)

Pension Plans and Other Postr_4

Pension Plans and Other Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Compensation And Retirement Disclosure [Abstract]
Defined contribution pension and retirement savings plans total expense	$ 22.2	$ 21.3

Earnings Per Common Share - Com

Earnings Per Common Share - Computations of Basic Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income available to common shareholders:
Net income	$ 482,742	$ 352,610
Less: Preferred stock dividends	(18,130)	(18,130)
Net income available to common equity	464,612	334,480
Less: Income attributable to unvested stock-based compensation awards	(2,526)	(1,732)
Net income available to common shareholders	$ 462,086	$ 332,748
Weighted-average shares outstanding:
Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards	138,637	149,470
Less: Unvested stock-based compensation awards	(748)	(782)
Weighted-average shares outstanding	137,889	148,688
Basic earnings per common share	$ 3.35	$ 2.24

Earnings Per Common Share - C_2

Earnings Per Common Share - Computations of Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Net income available to common equity	$ 464,612	$ 334,480
Less: Income attributable to unvested stock-based compensation awards	(2,526)	(1,731)
Net income available to common shareholders	$ 462,086	$ 332,749
Adjusted weighted-average shares outstanding:
Common and unvested stock-based compensation awards	138,637	149,470
Less: Unvested stock-based compensation awards	(748)	(782)
Plus: Incremental shares from assumed conversion of stock-based compensation awards and warrants to purchase common stock	31	217
Adjusted weighted-average shares outstanding	137,920	148,905
Diluted earnings per common share	$ 3.35	$ 2.23

Earnings Per Common Share - Add

Earnings Per Common Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share	280,818	237,584

Comprehensive Income - Componen

Comprehensive Income - Components of Other Comprehensive Income (Loss) and Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	$ (569,328)	$ (493,290)
Cumulative effect of change in accounting principles — equity securities, before tax		(22,795)
Unrealized holding gains (losses), net, before tax	113,805	(145,457)
Foreign currency translation adjustment, before tax	348	1,632
Unrealized gains (losses) on cash flow hedges, before tax	54,347	(14,719)
Total other comprehensive income (loss) before reclassifications, before tax	168,500	(158,544)
Amortization of unrealized holding losses on held-to-maturity ("HTM") securities, before tax	928	810
Losses realized in net income, before tax	7
Accretion of net gain on terminated cash flow hedges, before tax	(28)	(28)
Net yield adjustment from cash flow hedges currently in effect, before tax	6,625	580
Amortization of prior service credit, before tax	(1,050)	(1,050)
Amortization of actuarial losses, before tax	4,150	10,900
Total other comprehensive income (loss), before tax	179,132	(147,332)
Ending balance, before tax	(390,196)	(663,417)
Beginning balance, tax	149,247	129,476
Cumulative effect of change in accounting principles — equity securities, tax		5,942
Unrealized holding gains (losses), net, tax	(29,902)	44,176
Foreign currency translation adjustment, tax	(73)	(342)
Unrealized gains (losses) on cash flow hedges, tax	(14,288)	3,870
Total other comprehensive income (loss) before reclassifications, tax	(44,263)	47,704
Amortization of unrealized holding losses on held-to-maturity ('HTM') securities, tax	(245)	(213)
Losses realized in net income, tax	(2)
Accretion of net gain on terminated cash flow hedges, tax	7	7
Net yield adjustment from cash flow hedges currently in effect, tax	(1,742)	(152)
Amortization of prior service credit, tax	276	276
Amortization of actuarial losses, tax	(1,091)	(2,866)
Total other comprehensive income (loss), tax	(47,060)	44,756
Ending balance, tax	102,187	180,174
Beginning balance, net of tax	(420,081)	(363,814)
Cumulative effect of change in accounting principle — equity securities		(16,853)
Unrealized holding gains (losses), net of tax	83,903	(101,281)
Foreign currency translation adjustment	275	1,290
Unrealized gains (losses) on cash flow hedges, net of tax	40,059	(10,849)
Total other comprehensive income (loss) before reclassifications, net of tax	124,237	(110,840)
Amortization of unrealized holding losses on held-to-maturity ('HTM') securities, net of tax	683	597
Losses realized in net income, net of tax	5
Accretion of net gain on terminated cash flow hedges, net of tax	(21)	(21)
Net yield adjustment from cash flow hedges currently in effect, net of tax	4,883	428
Amortization of prior service credit, net of tax	(774)	(774)
Amortization of actuarial losses, net of tax	3,059	8,034
Total other comprehensive income (loss)	132,072	(102,576)
Ending balance, net of tax	(288,009)	(483,243)
Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	(200,107)	(59,957)
Cumulative effect of change in accounting principles — equity securities, before tax		(22,795)
Unrealized holding gains (losses), net, before tax	113,805	(145,457)
Total other comprehensive income (loss) before reclassifications, before tax	113,805	(145,457)
Amortization of unrealized holding losses on held-to-maturity ("HTM") securities, before tax	928	810
Losses realized in net income, before tax	7
Total other comprehensive income (loss), before tax	114,740	(144,647)
Ending balance, before tax	(85,367)	(227,399)
Total other comprehensive income (loss)	84,591
Defined Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	(354,502)	(413,168)
Amortization of prior service credit, before tax	(1,050)	(1,050)
Amortization of actuarial losses, before tax	4,150	10,900
Total other comprehensive income (loss), before tax	3,100	9,850
Ending balance, before tax	(351,402)	(403,318)
Total other comprehensive income (loss)	2,285
Other [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance, before tax	(14,719)	(20,165)
Foreign currency translation adjustment, before tax	348	1,632
Unrealized gains (losses) on cash flow hedges, before tax	54,347	(14,719)
Total other comprehensive income (loss) before reclassifications, before tax	54,695	(13,087)
Accretion of net gain on terminated cash flow hedges, before tax	(28)	(28)
Net yield adjustment from cash flow hedges currently in effect, before tax	6,625	580
Total other comprehensive income (loss), before tax	61,292	(12,535)
Ending balance, before tax	$ 46,573	$ (32,700)

Comprehensive Income - Accumula

Comprehensive Income - Accumulated Other Comprehensive Income (Loss), Net (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 15,460,191	$ 16,250,819
Net gain during period	132,072	(102,576)
Ending balance	15,587,529	15,709,694
Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(147,526)
Net gain during period	84,591
Ending balance	(62,935)
Defined Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(261,303)
Net gain during period	2,285
Ending balance	(259,018)
Accumulated Other Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(11,252)
Net gain during period	45,196
Ending balance	33,944
Accumulated Other Comprehensive Income (Loss), Net [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(420,081)	(363,814)
Net gain during period	132,072
Ending balance	$ (288,009)	$ (483,243)

Derivative Financial Instrume_3

Derivative Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Derivative [Line Items]
Notional amounts of derivative contracts entered into for trading account purposes	$ 34,200,000,000		$ 19,850,000,000
Net unrealized pre-tax gains related to hedged loans held for sale, commitments to originate loans for sale and commitments to sell loans	16,000,000		18,000,000
Aggregate fair value of derivative financial instruments in a liability position	20,000,000		21,000,000
Net liability positions with counterparties	20,000,000		21,000,000
Aggregate fair value of derivative financial instruments in asset position	7,000,000		18,000,000
Net fair value of derivative financial instruments in a net asset position	7,000,000		18,000,000
Collateral relating to net asset positions	3,000,000		16,000,000
Counterparties [Member]
Derivative [Line Items]
Post collateral requirements relating to positions	20,000,000		18,000,000
Clearinghouse Credit Facilities [Member]
Derivative [Line Items]
Amount of initial margin posted	71,000,000		65,000,000
Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Increase decrease in net interest income due to interest rate swap agreements	(13,000,000)	$ 1,000,000
Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amounts of derivative contracts entered into for trading account purposes	43,300,000,000		42,900,000,000
Foreign Currency and Other Option and Futures Contracts [Member]
Derivative [Line Items]
Notional amounts of derivative contracts entered into for trading account purposes	832,000,000		$ 763,000,000
Credit Risk Derivative [Member]
Derivative [Line Items]
Fair value of additional collateral to be posted for derivative financial instruments	$ 0

Derivative Financial Instrume_4

Derivative Financial Instruments - Information about Interest Rate Swap Agreements (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Notional Amount	$ 34,200,000,000	$ 19,850,000,000
Average Maturity (in years)	1 year 7 months 6 days	1 year 8 months 12 days
Estimated Fair Value Gain (Loss)	$ (16,924,000)	$ 5,530,000
Interest Payments On Variable Rate Commercial Real Estate Loans [Member] | Cash Flow Hedges [Member]
Derivative [Line Items]
Notional Amount	$ 29,750,000,000	$ 15,400,000,000
Average Maturity (in years)	1 year 4 months 24 days	1 year 3 months 18 days
Weighted-Average Rate, Fixed	2.29%	1.52%
Weighted-Average Rate, Variable	2.49%	2.35%
Estimated Fair Value Gain (Loss)	$ (12,534,000)	$ 1,311,000
Fixed Rate Long-Term Borrowings [Member] | Fair Value Hedges [Member]
Derivative [Line Items]
Notional Amount	$ 4,450,000,000	$ 4,450,000,000
Average Maturity (in years)	2 years 7 months 6 days	2 years 9 months 18 days
Weighted-Average Rate, Fixed	2.47%	2.47%
Weighted-Average Rate, Variable	3.04%	3.02%
Estimated Fair Value Gain (Loss)	$ (4,390,000)	$ 4,219,000

Derivative Financial Instrume_5

Derivative Financial Instruments - Information about Interest Rate Swap Agreements (Parenthetical) (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Notional Amount	$ 34,200,000,000	$ 19,850,000,000
Forward-Starting Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Notional Amount	16,400,000,000	12,600,000,000
Fair Value Hedges [Member]
Derivative [Line Items]
Reduction of estimated fair value losses on hedging instruments	11,900,000	54,700,000
Cash Flow Hedges [Member]
Derivative [Line Items]
Reduction of estimated fair value losses on hedging instruments	$ 65,700,000	$ 9,100,000

Derivative Financial Instrume_6

Derivative Financial Instruments - Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 220,442	$ 148,862
Liability Derivatives, Fair Value	122,846	190,686
Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	219,030	142,242
Liability Derivatives, Fair Value	102,242	184,252
Fair Value Hedges [Member] | Derivatives Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	1,412	6,620
Liability Derivatives, Fair Value	20,604	6,434
Interest Rate Swap Agreements [Member] | Fair Value Hedges [Member] | Derivatives Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	267	5,530
Liability Derivatives, Fair Value	17,191
Commitments to Sell Real Estate Loans [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	3,687	3,702
Liability Derivatives, Fair Value	2,843	4,535
Commitments to Sell Real Estate Loans [Member] | Fair Value Hedges [Member] | Derivatives Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	1,145	1,090
Liability Derivatives, Fair Value	3,413	6,434
Mortgage-Related Commitments to Originate Real Estate Loans for Sale [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	8,059	9,304
Liability Derivatives, Fair Value	626	1,592
Interest Rate Contracts [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	199,404	118,687
Liability Derivatives, Fair Value	92,383	169,255
Foreign Exchange and Other Option and Futures Contracts [Member] | Derivatives Not Designated and Qualifying as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	7,880	10,549
Liability Derivatives, Fair Value	$ 6,390	$ 8,870

Derivative Financial Instrume_7

Derivative Financial Instruments - Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Offsetting [Abstract]
Reduction in estimated fair value of interest rate contracts in asset position	$ (88.1)	$ (170.7)
Reduction in estimated fair value of interest rate contracts in liability position	$ (122.8)	$ (49.7)

Derivative Financial Instrume_8

Derivative Financial Instruments - Information about Fair Values of Derivative Instruments in Consolidated Statement of Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, Derivatives	$ 4,324	$ 1,026
Interest Rate Swap Agreements [Member] | Fixed Rate Long-Term Borrowings [Member] | Derivatives Designated and Qualifying as Hedging Instruments [Member] | Fair Value Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives in fair value hedging relationships, Derivatives	34,180	(42,390)
Derivatives in fair value hedging relationships, Hedged item	(34,014)	42,370
Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, Derivatives	2,711	(1,605)
Foreign Exchange and Other Option and Futures Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, Derivatives	$ 1,613	$ 2,631

Derivative Financial Instrume_9

Derivative Financial Instruments - Information about Hedged Items Included in Consolidated Balance Sheet (Detail) - Long-term Debt [Member] - Derivatives Designated and Qualifying as Hedging Instruments [Member] - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Carrying Amount [Member]
Derivatives, Fair Value [Line Items]
Hedged Item	$ 4,428,645	$ 4,394,109
Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount [Member]
Derivatives, Fair Value [Line Items]
Hedged Item	$ (17,088)	$ (51,102)

Variable Interest Entities an_2

Variable Interest Entities and Asset Securitizations - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Variable Interest Entity Disclosure [Abstract]
Loss on securitization of assets	$ 0	$ 0
Other assets for its "investment" in the common securities recognized by the company of various trusts	23,000,000		$ 23,000,000
Total assets of partnerships in which the company invested	1,100,000,000		1,100,000,000
Maximum exposure to loss of investments in real estate partnerships		517,000,000	523,000,000
Unfunded commitments included in company's maximum exposure to loss of investments in real estate partnerships		278,000,000	$ 280,000,000
Investments amortized to income tax expense	17,000,000	13,000,000
Federal tax credits and other federal tax benefits recognized	$ 20,000,000	$ 16,000,000

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Estimated Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Trading account assets	$ 276,322	$ 185,584
Investment securities	8,325,584	8,682,509
U.S. Treasury and Federal Agencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	1,139,428	1,336,931
Obligations of States and Political Subdivisions [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	1,181	1,659
Government Issued or Guaranteed [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	7,053,907	7,216,991
Other Debt Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	131,052	126,906
Fair Value Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Trading account assets	276,322	185,584
Investment securities	8,325,584	8,682,509
Equity securities	76,586	93,917
Real estate loans held for sale	344,350	551,697
Other assets	13,158	19,626
Total assets	9,036,000	9,533,333
Trading account liabilities	98,771	178,125
Other liabilities	24,073	12,561
Total liabilities	122,844	190,686
Fair Value Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Trading account assets	46,521	46,018
Equity securities	43,301	71,989
Total assets	89,822	118,007
Fair Value Measurements, Recurring [Member] | Significant Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Trading account assets	229,801	139,566
Investment securities	8,325,568	8,682,487
Equity securities	33,285	21,928
Real estate loans held for sale	344,350	551,697
Other assets	5,099	10,322
Total assets	8,938,103	9,406,000
Trading account liabilities	98,771	178,125
Other liabilities	23,447	10,969
Total liabilities	122,218	189,094
Fair Value Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	16	22
Other assets	8,059	9,304
Total assets	8,075	9,326
Other liabilities	626	1,592
Total liabilities	626	1,592
Fair Value Measurements, Recurring [Member] | U.S. Treasury and Federal Agencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	1,139,428	1,336,931
Fair Value Measurements, Recurring [Member] | U.S. Treasury and Federal Agencies [Member] | Significant Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	1,139,428	1,336,931
Fair Value Measurements, Recurring [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	1,181	1,659
Fair Value Measurements, Recurring [Member] | Obligations of States and Political Subdivisions [Member] | Significant Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	1,181	1,659
Fair Value Measurements, Recurring [Member] | Government Issued or Guaranteed [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	7,053,907	7,216,991
Fair Value Measurements, Recurring [Member] | Government Issued or Guaranteed [Member] | Significant Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	7,053,907	7,216,991
Fair Value Measurements, Recurring [Member] | Privately Issued Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	16	22
Fair Value Measurements, Recurring [Member] | Privately Issued Mortgage-Backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	16	22
Fair Value Measurements, Recurring [Member] | Other Debt Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	131,052	126,906
Fair Value Measurements, Recurring [Member] | Other Debt Securities [Member] | Significant Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investment securities	$ 131,052	$ 126,906

Fair Value Measurements - Ass_2

Fair Value Measurements - Assets and Liabilities Measured at Estimated Fair Value on Recurring Basis (Parenthetical) (Detail) - USD ($)	Mar. 31, 2019	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Transfer of asset from level 1 to 2	$ 0	$ 0
Transfer of asset from level 2 to 1	0	0
Transfer of liabilities from level 1 to 2	0	0
Transfer of liabilities from level 2 to 1	$ 0	$ 0

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Level 3 Assets and Liabilities Measured at Estimated Fair Value on Recurring Basis (Detail) - Fair Value Measurements, Recurring [Member] - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Privately Issued Mortgage-Backed Securities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 22	$ 28
Total gains (losses) realized/unrealized:
Settlements	(6)	(1)
Ending Balance	16	27
Other Assets and Other Liabilities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	7,712	8,303
Total gains (losses) realized/unrealized:
Included in earnings	16,546	8,130
Transfers out of Level 3	(16,825)	(7,673)
Ending Balance	7,433	8,760
Changes in unrealized gains included in earnings related to assets still held at end of period	$ 8,525	$ 8,778

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurement Input [Extensible List]	us-gaap:MeasurementInputComparabilityAdjustmentMember
Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Discount rates for fair value estimations	15.00%
Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Discount rates for fair value estimations	90.00%
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Change in fair value of nonrecurring fair value measured loans for charge-offs and impairment reserves	$ 20	$ 27
Fair Value, Measurements, Nonrecurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans measured at fair value on nonrecurring basis	199	178	$ 268
Assets taken in foreclosure of defaulted loans measured at fair value on a nonrecurring basis	9	19
Fair Value, Measurements, Nonrecurring [Member] | Significant Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans measured at fair value on nonrecurring basis	121	97	120
Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans measured at fair value on nonrecurring basis	$ 78	$ 81	$ 148

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative Information Related to Significant Unobservable Inputs (Detail) - Fair Value Measurements, Recurring [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Privately Issued Mortgage-Backed Securities [Member] | Two Independent Pricing Quotes [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Recurring fair value measurements for certain Level 3 Assets and Liabilities	$ 16	$ 22
Other Assets and Other Liabilities [Member] | Discounted Cash Flows [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Recurring fair value measurements for certain Level 3 Assets and Liabilities	$ 7,433	$ 7,712
Other Assets and Other Liabilities [Member] | Discounted Cash Flows [Member] | Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Commitment expirations	0.00%	0.00%
Other Assets and Other Liabilities [Member] | Discounted Cash Flows [Member] | Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Commitment expirations	94.00%	95.00%
Other Assets and Other Liabilities [Member] | Discounted Cash Flows [Member] | Weighted Average [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Commitment expirations	17.00%	13.00%

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Amounts and Estimated Fair Value for Financial Instrument Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Financial assets:
Interest-bearing deposits at banks	$ 7,602,897	$ 8,105,197
Trading account assets	276,322	185,584
Investment securities	12,536,840	12,692,813
Loans and leases:
Allowance for credit losses	(1,019,337)	(1,019,444)	$ (1,019,671)	$ (1,017,198)
Loans and leases, net	87,620,546	87,447,033
Financial liabilities:
Noninterest-bearing deposits	(29,966,753)	(32,256,668)
Savings and interest-checking deposits	(52,932,297)	(50,963,744)
Time deposits	(6,501,509)	(6,124,254)
Deposits at Cayman Islands office	(1,069,191)	(811,906)
Long-term borrowings	(8,476,024)	(8,444,914)
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	1,267,260	1,605,439
Interest-bearing deposits at banks	7,602,897	8,105,197
Trading account assets	276,322	185,584
Investment securities	12,536,840	12,692,813
Loans and leases:
Commercial loans and leases	23,090,204	22,977,976
Commercial real estate loans	34,690,930	34,363,556
Residential real estate loans	16,769,933	17,154,446
Consumer loans	14,088,816	13,970,499
Allowance for credit losses	(1,019,337)	(1,019,444)
Loans and leases, net	87,620,546	87,447,033
Accrued interest receivable	374,084	353,965
Financial liabilities:
Noninterest-bearing deposits	(29,966,753)	(32,256,668)
Savings and interest-checking deposits	(52,932,297)	(50,963,744)
Time deposits	(6,501,509)	(6,124,254)
Deposits at Cayman Islands office	(1,069,191)	(811,906)
Short-term borrowings	(3,602,566)	(4,398,378)
Long-term borrowings	(8,476,024)	(8,444,914)
Accrued interest payable	(80,322)	(95,274)
Trading account liabilities	(98,771)	(178,125)
Other financial instruments:
Commitments to originate real estate loans for sale	7,433	7,712
Commitments to sell real estate loans	(1,424)	(6,177)
Other credit-related commitments	(126,811)	(131,688)
Interest rate swap agreements used for interest rate risk management	(16,924)	5,530
Estimate Fair Value [Member]
Financial assets:
Cash and cash equivalents	1,267,260	1,605,439
Interest-bearing deposits at banks	7,602,897	8,105,197
Trading account assets	276,322	185,584
Investment securities	12,521,737	12,631,656
Loans and leases:
Commercial loans and leases	22,755,670	22,587,387
Commercial real estate loans	34,424,612	33,832,558
Residential real estate loans	16,764,418	16,974,545
Consumer loans	14,018,581	13,819,545
Loans and leases, net	87,963,281	87,214,035
Accrued interest receivable	374,084	353,965
Financial liabilities:
Noninterest-bearing deposits	(29,966,753)	(32,256,668)
Savings and interest-checking deposits	(52,932,297)	(50,963,744)
Time deposits	(6,598,274)	(6,201,957)
Deposits at Cayman Islands office	(1,069,191)	(811,906)
Short-term borrowings	(3,602,566)	(4,398,378)
Long-term borrowings	(8,511,141)	(8,385,289)
Accrued interest payable	(80,322)	(95,274)
Trading account liabilities	(98,771)	(178,125)
Other financial instruments:
Commitments to originate real estate loans for sale	7,433	7,712
Commitments to sell real estate loans	(1,424)	(6,177)
Other credit-related commitments	(126,811)	(131,688)
Interest rate swap agreements used for interest rate risk management	(16,924)	5,530
Estimate Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets:
Cash and cash equivalents	1,194,318	1,528,302
Trading account assets	46,521	46,018
Investment securities	43,301	71,989
Estimate Fair Value [Member] | Significant Observable Inputs (Level 2) [Member]
Financial assets:
Cash and cash equivalents	72,942	77,137
Interest-bearing deposits at banks	7,602,897	8,105,197
Trading account assets	229,801	139,566
Investment securities	12,378,816	12,456,467
Loans and leases:
Commercial real estate loans	166,019	346,775
Residential real estate loans	3,877,095	3,920,447
Loans and leases, net	4,043,114	4,267,222
Accrued interest receivable	374,084	353,965
Financial liabilities:
Noninterest-bearing deposits	(29,966,753)	(32,256,668)
Savings and interest-checking deposits	(52,932,297)	(50,963,744)
Time deposits	(6,598,274)	(6,201,957)
Deposits at Cayman Islands office	(1,069,191)	(811,906)
Short-term borrowings	(3,602,566)	(4,398,378)
Long-term borrowings	(8,511,141)	(8,385,289)
Accrued interest payable	(80,322)	(95,274)
Trading account liabilities	(98,771)	(178,125)
Other financial instruments:
Commitments to sell real estate loans	(1,424)	(6,177)
Interest rate swap agreements used for interest rate risk management	(16,924)	5,530
Estimate Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets:
Investment securities	99,620	103,200
Loans and leases:
Commercial loans and leases	22,755,670	22,587,387
Commercial real estate loans	34,258,593	33,485,783
Residential real estate loans	12,887,323	13,054,098
Consumer loans	14,018,581	13,819,545
Loans and leases, net	83,920,167	82,946,813
Other financial instruments:
Commitments to originate real estate loans for sale	7,433	7,712
Other credit-related commitments	$ (126,811)	$ (131,688)

Commitments and Contingencies -

Commitments and Contingencies - Company's Significant Commitments (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Commitments to extend credit
Home equity lines of credit	$ 5,529,111	$ 5,484,197
Commercial real estate loans to be sold	199,722	229,401
Other commercial real estate	7,331,360	7,556,722
Residential real estate loans to be sold	314,402	245,211
Other residential real estate	277,708	219,351
Commercial and other	14,900,142	14,363,803
Standby letters of credit	2,246,864	2,326,991
Commercial letters of credit	59,464	55,808
Financial guarantees and indemnification contracts	3,703,612	3,529,136
Commitments to sell real estate loans	$ 746,307	$ 940,692

Commitments and Contingencies_2

Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2018
Loss Contingencies [Line Items]
Commitments to extend credit to commercial customers	$ 8,700,000,000			$ 8,600,000,000
Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program	3,500,000,000			$ 3,400,000,000
Payment of legal settlement expense		$ 200,000,000
Increased recorded liability for legal-related matters	50,000,000		$ 135,000,000
Minimum [Member]
Loss Contingencies [Line Items]
Range of reasonably possible losses	0
Maximum [Member]
Loss Contingencies [Line Items]
Range of reasonably possible losses	$ 100,000,000

Segment Information - Informati

Segment Information - Information about Company's Segments (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Net Income (Loss)	$ 482,742	$ 352,610
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	1,550,825	1,434,213
Business Banking [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	43,271	37,718
Business Banking [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	139,322	127,884
Business Banking [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	856	918
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	132,218	125,465
Commercial Banking [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	267,490	266,396
Commercial Banking [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	840	850
Commercial Real Estate [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	117,498	108,303
Commercial Real Estate [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	219,173	202,607
Commercial Real Estate [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	354	340
Discretionary Portfolio [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	39,172	19,739
Discretionary Portfolio [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	63,917	50,038
Discretionary Portfolio [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	(9,299)	(10,832)
Residential Mortgage Banking [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	12,941	14,946
Residential Mortgage Banking [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	83,761	82,458
Residential Mortgage Banking [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	14,514	15,421
Retail Banking [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	145,066	123,380
Retail Banking [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	430,891	393,476
Retail Banking [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	2,511	2,865
All Other [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)	(7,424)	(76,941)
All Other [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues	346,271	311,354
All Other [Member] | Intersegment Activity Eliminated in Consolidated Totals [Member]
Segment Reporting Information [Line Items]
Total Revenues	$ (9,776)	$ (9,562)

Segment Information - Summary o

Segment Information - Summary of Segment Information (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Segment Reporting Information [Line Items]
Average Total Assets	$ 116,839	$ 116,959	$ 117,684
Business Banking [Member]
Segment Reporting Information [Line Items]
Average Total Assets	5,702	5,631	5,681
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Average Total Assets	27,858	26,626	26,482
Commercial Real Estate [Member]
Segment Reporting Information [Line Items]
Average Total Assets	23,572	22,885	22,811
Discretionary Portfolio [Member]
Segment Reporting Information [Line Items]
Average Total Assets	30,341	32,123	34,095
Residential Mortgage Banking [Member]
Segment Reporting Information [Line Items]
Average Total Assets	2,071	2,161	2,278
Retail Banking [Member]
Segment Reporting Information [Line Items]
Average Total Assets	14,403	13,656	13,377
All Other [Member]
Segment Reporting Information [Line Items]
Average Total Assets	$ 12,892	$ 13,877	$ 12,960

Segment Information - Summary_2

Segment Information - Summary of Segment Information (Parenthetical) (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting [Abstract]
Taxable-equivalent adjustment	$ 5,967,000	$ 4,809,000

Relationship with Bayview Len_2

Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P. - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jan. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Loan facility carrying amount	$ 8,476,024,000			$ 8,444,914,000
Bayview Lending Group [Member]
Schedule of Equity Method Investments [Line Items]
Minority interest in Bayview Lending Group LLC	20.00%
Carrying value of minority interest investment in Bayview Lending Group LLC	$ 0
Bayview Lending Group [Member] | Other Revenues From Operations [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	37,000,000	$ 23,000,000
Bayview Lending Group and Bayview Financial [Member]
Schedule of Equity Method Investments [Line Items]
Outstanding principal balances of mortgage servicing rights	2,500,000,000			2,500,000,000
Revenue from contract with customer	3,000,000	4,000,000
Bayview Financial [Member]
Schedule of Equity Method Investments [Line Items]
Outstanding principal balances of residential mortgage loans from Bayview Financial	54,900,000,000			56,800,000,000
Revenues from sub-servicing	28,000,000	$ 30,000,000
Investment securities in held-to-maturity portfolio securitized by Bayview Financial	108,000,000			$ 113,000,000
Addition on outstanding principal balances of residential mortgage loans from Bayview Financial			$ 7,900,000,000
Bayview Financial [Member] | Syndicated Loan Facility [Member]
Schedule of Equity Method Investments [Line Items]
Loan facility carrying amount	738,000,000
Bayview Financial [Member] | Syndicated Loan Facility [Member] | M&T Bank [Member]
Schedule of Equity Method Investments [Line Items]
Loan facility carrying amount	$ 94,000,000

Recent Accounting Developments

Recent Accounting Developments - Additional Information (Detail) $ in Thousands	Mar. 31, 2019USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Recognized right of use asset	$ 392,847
Recognizing lease liabilities	$ 419,958
ASU 2016-02 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Lessee, operating lease term	12 months
Recognized right of use asset	$ 394,000
Recognizing lease liabilities	$ 399,000