Fair Value of Assets & Liabilities - Summary Of Book Value And Estimated Fair Value Of Financial Instruments (Details) - USD ($) $ in Thousands		Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		$ 29,520,061	$ 27,355,108
Short-term financial assets:
Interest-bearing cash		593,180	1,277,611
Federal funds sold		50,705	237,591
Securities purchased under agreements to resell		602,919	386,443
Trading securities		1,668,942	1,448,168
Loans held-for-sale	[1]	447,106	679,149
Securities available-for-sale		4,415,609	4,626,470
Securities held-to-maturity		10,000	10,000
Derivative assets		185,521	81,475
Other assets:
Total assets		42,171,770	40,832,258
Liabilities:
Trading Liabilities		558,347	335,380
Short-term financial liabilities:
Federal funds purchased		666,007	256,567
Securities sold under agreements to repurchase		764,308	762,592
Other short-term borrowings		865,347	114,764
Term borrowings:
Other long term borrowings		1,186,646	1,170,963
Derivative liabilities		88,485	133,713
Total liabilities		37,245,689	36,046,878
Fair Value, Inputs, Level 3 | FHLB-Cincinnati Stock
Term borrowings:
Restricted investments		71,000	87,900
Fair Value, Inputs, Level 3 | FRB Stock
Term borrowings:
Restricted investments		130,700	130,700
Reported Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		29,520,061	27,355,108
Short-term financial assets:
Interest-bearing cash		593,180	1,277,611
Federal funds sold		50,705	237,591
Securities purchased under agreements to resell		602,919	386,443
Total short-term financial assets		1,246,804	1,901,645
Trading securities		1,668,942	1,448,168
Loans held-for-sale		447,106	679,149
Securities available-for-sale		4,415,609	4,626,470
Securities held-to-maturity		10,000	10,000
Derivative assets		185,521	81,475
Other assets:
Tax credit investments		165,288	163,300
Deferred compensation assets		43,577	37,771
Equity, mutual funds, and other		224,075	240,780
Total other assets		432,940	441,851
Total assets		37,926,983	36,543,866
Liabilities:
Defined maturity		4,398,526	4,105,777
Trading Liabilities		558,347	335,380
Short-term financial liabilities:
Federal funds purchased		666,007	256,567
Securities sold under agreements to repurchase		764,308	762,592
Other short-term borrowings		865,347	114,764
Short Term Financial Liabilities		2,295,662	1,133,923
Term borrowings:
Real estate investment trust-preferred		46,202	46,168
Term borrowings - new market tax credit investment		2,699	2,699
Secured Borrowings		22,343	19,588
Junior subordinated debentures		143,924	143,255
Other long term borrowings		971,478	959,253
Total term borrowings		1,186,646	1,170,963
Derivative liabilities		88,485	133,713
Total liabilities		8,527,666	6,879,756
Reported Value Measurement | Commercial, financial, and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		18,938,173	16,415,381
Reported Value Measurement | Commercial Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		3,828,078	3,999,559
Reported Value Measurement | Consumer Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		6,087,225	6,223,077
Reported Value Measurement | Permanent Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		184,377	211,448
Reported Value Measurement | Credit Card and Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		482,208	505,643
Reported Value Measurement | Mortgage loans (elected fair value)
Short-term financial assets:
Loans held-for-sale		15,092	16,273
Reported Value Measurement | Government guaranteed loans (SBA and USDA)
Short-term financial assets:
Loans held-for-sale		369,081	578,291
Reported Value Measurement | Other consumer loans- LOCOM
Short-term financial assets:
Loans held-for-sale		5,809	25,134
Reported Value Measurement | Mortgage loans- LOCOM
Short-term financial assets:
Loans held-for-sale		57,124	59,451
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		29,628,161	27,364,329
Short-term financial assets:
Interest-bearing cash		593,180	1,277,611
Federal funds sold		50,705	237,591
Securities purchased under agreements to resell		602,919	386,443
Total short-term financial assets		1,246,804	1,901,645
Trading securities		1,668,942	1,448,168
Loans held-for-sale		449,775	684,349
Securities available-for-sale		4,415,609	4,626,470
Securities held-to-maturity		9,923	9,843
Derivative assets		185,521	81,475
Other assets:
Tax credit investments		162,859	159,452
Deferred compensation assets		43,577	37,771
Equity, mutual funds, and other		224,075	240,780
Total other assets		430,511	438,003
Total assets		38,035,246	36,554,282
Liabilities:
Defined maturity		4,401,460	4,082,822
Trading Liabilities		558,347	335,380
Short-term financial liabilities:
Federal funds purchased		666,007	256,567
Securities sold under agreements to repurchase		764,308	762,592
Other short-term borrowings		865,347	114,764
Short Term Financial Liabilities		2,295,662	1,133,923
Term borrowings:
Real estate investment trust-preferred		47,000	47,000
Term borrowings - new market tax credit investment		2,690	2,664
Secured Borrowings		22,343	19,588
Junior subordinated debentures		138,947	134,266
Other long term borrowings		971,293	960,483
Total term borrowings		1,182,273	1,164,001
Derivative liabilities		88,485	133,713
Total liabilities		8,526,227	6,849,839
Loan commitments		2,646	2,551
Standby and other commitments		5,333	5,043
Estimate of Fair Value Measurement | Commercial, financial, and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		19,041,553	16,438,272
Estimate of Fair Value Measurement | Commercial Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		3,842,446	3,997,736
Estimate of Fair Value Measurement | Consumer Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		6,070,685	6,194,066
Estimate of Fair Value Measurement | Permanent Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		195,113	227,254
Estimate of Fair Value Measurement | Credit Card and Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		478,364	507,001
Estimate of Fair Value Measurement | Mortgage loans (elected fair value)
Short-term financial assets:
Loans held-for-sale		15,092	16,273
Estimate of Fair Value Measurement | Government guaranteed loans (SBA and USDA)
Short-term financial assets:
Loans held-for-sale		371,750	583,491
Estimate of Fair Value Measurement | Other consumer loans- LOCOM
Short-term financial assets:
Loans held-for-sale		5,809	25,134
Estimate of Fair Value Measurement | Mortgage loans- LOCOM
Short-term financial assets:
Loans held-for-sale		57,124	59,451
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Short-term financial assets:
Interest-bearing cash		593,180	1,277,611
Federal funds sold		0	0
Securities purchased under agreements to resell		0	0
Total short-term financial assets		593,180	1,277,611
Trading securities		0	0
Loans held-for-sale		0	0
Securities available-for-sale		0	0
Securities held-to-maturity		0	0
Derivative assets		38,134	28,826
Other assets:
Tax credit investments		0	0
Deferred compensation assets		43,577	37,771
Equity, mutual funds, and other		22,419	22,248
Total other assets		65,996	60,019
Total assets		697,310	1,366,456
Liabilities:
Defined maturity		0	0
Trading Liabilities		0	0
Short-term financial liabilities:
Federal funds purchased		0	0
Securities sold under agreements to repurchase		0	0
Other short-term borrowings		0	0
Short Term Financial Liabilities		0	0
Term borrowings:
Real estate investment trust-preferred		0	0
Term borrowings - new market tax credit investment		0	0
Secured Borrowings		0	0
Junior subordinated debentures		0	0
Other long term borrowings		0	0
Total term borrowings		0	0
Derivative liabilities		37,991	30,236
Total liabilities		37,991	30,236
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Commercial, financial, and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Commercial Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Consumer Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Permanent Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Credit Card and Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Mortgage loans (elected fair value)
Short-term financial assets:
Loans held-for-sale		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Government guaranteed loans (SBA and USDA)
Short-term financial assets:
Loans held-for-sale		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Other consumer loans- LOCOM
Short-term financial assets:
Loans held-for-sale		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1 | Mortgage loans- LOCOM
Short-term financial assets:
Loans held-for-sale		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Short-term financial assets:
Interest-bearing cash		0	0
Federal funds sold		50,705	237,591
Securities purchased under agreements to resell		602,919	386,443
Total short-term financial assets		653,624	624,034
Trading securities		1,667,687	1,446,644
Loans held-for-sale		376,539	588,898
Securities available-for-sale		4,397,817	4,616,568
Securities held-to-maturity		0	0
Derivative assets		147,387	52,649
Other assets:
Tax credit investments		0	0
Deferred compensation assets		0	0
Equity, mutual funds, and other		0	0
Total other assets		0	0
Total assets		7,243,054	7,328,793
Liabilities:
Defined maturity		4,401,460	4,082,822
Trading Liabilities		558,347	335,380
Short-term financial liabilities:
Federal funds purchased		666,007	256,567
Securities sold under agreements to repurchase		764,308	762,592
Other short-term borrowings		865,347	114,764
Short Term Financial Liabilities		2,295,662	1,133,923
Term borrowings:
Real estate investment trust-preferred		0	0
Term borrowings - new market tax credit investment		0	0
Secured Borrowings		0	0
Junior subordinated debentures		0	0
Other long term borrowings		971,293	960,483
Total term borrowings		971,293	960,483
Derivative liabilities		23,949	71,937
Total liabilities		8,250,711	6,584,545
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Commercial, financial, and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Commercial Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Consumer Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Permanent Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Credit Card and Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Mortgage loans (elected fair value)
Short-term financial assets:
Loans held-for-sale		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Government guaranteed loans (SBA and USDA)
Short-term financial assets:
Loans held-for-sale		370,730	582,476
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Other consumer loans- LOCOM
Short-term financial assets:
Loans held-for-sale		5,809	6,422
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2 | Mortgage loans- LOCOM
Short-term financial assets:
Loans held-for-sale		0	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		29,628,161	27,364,329
Short-term financial assets:
Interest-bearing cash		0	0
Federal funds sold		0	0
Securities purchased under agreements to resell		0	0
Total short-term financial assets		0	0
Trading securities		1,255	1,524
Loans held-for-sale		73,236	95,451
Securities available-for-sale		17,792	9,902
Securities held-to-maturity		9,923	9,843
Derivative assets		0	0
Other assets:
Tax credit investments		162,859	159,452
Deferred compensation assets		0	0
Equity, mutual funds, and other		201,656	218,532
Total other assets		364,515	377,984
Total assets		30,094,882	27,859,033
Liabilities:
Defined maturity		0	0
Trading Liabilities		0	0
Short-term financial liabilities:
Federal funds purchased		0	0
Securities sold under agreements to repurchase		0	0
Other short-term borrowings		0	0
Short Term Financial Liabilities		0	0
Term borrowings:
Real estate investment trust-preferred		47,000	47,000
Term borrowings - new market tax credit investment		2,690	2,664
Secured Borrowings		22,343	19,588
Junior subordinated debentures		138,947	134,266
Other long term borrowings		0	0
Total term borrowings		210,980	203,518
Derivative liabilities		26,545	31,540
Total liabilities		237,525	235,058
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Commercial, financial, and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		19,041,553	16,438,272
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Commercial Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		3,842,446	3,997,736
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Consumer Real Estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		6,070,685	6,194,066
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Permanent Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		195,113	227,254
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Credit Card and Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total loans, net of unearned income and allowance for loan losses		478,364	507,001
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Mortgage loans (elected fair value)
Short-term financial assets:
Loans held-for-sale		15,092	16,273
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Government guaranteed loans (SBA and USDA)
Short-term financial assets:
Loans held-for-sale		1,020	1,015
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Other consumer loans- LOCOM
Short-term financial assets:
Loans held-for-sale		0	18,712
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | Mortgage loans- LOCOM
Short-term financial assets:
Loans held-for-sale		57,124	59,451
Contractual Amount
Term borrowings:
Loan commitments		11,215,601	10,884,975
Standby and other commitments		$ 397,249	$ 446,958

[1] June 30, 2019 and December 31, 2018 include $6.7 million and $8.4 million, respectively, of held-for-sale consumer mortgage loans secured by residential real estate in process of foreclosure.