Segment Reporting (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) employee segment	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) employee
Segment Reporting [Abstract]
Number of reportable segments | segment	4
Income Statement Related Disclosures [Abstract]
Net interest income	$ 418,846	$ 480,751
Non-interest revenue	118,888	133,126
Non-interest expense	322,741	321,852
Pre-provision net revenue (PPNR)	214,993	292,025
Balance Sheet Related Disclosures [Abstract]
Loans, net of deferred fees and costs	43,309,877		$ 43,404,490
Total deposits	$ 50,580,242		$ 50,739,185
Total full-time equivalent employees | employee	4,732		4,798
Operating Segments | Wholesale Banking
Income Statement Related Disclosures [Abstract]
Net interest income	$ 183,666	199,100
Non-interest revenue	11,325	15,900
Non-interest expense	34,729	33,848
Pre-provision net revenue (PPNR)	160,262	181,152
Balance Sheet Related Disclosures [Abstract]
Loans, net of deferred fees and costs	25,483,782		$ 25,506,870
Total deposits	$ 13,196,663		$ 13,847,833
Total full-time equivalent employees | employee	331		334
Operating Segments | Community Banking
Income Statement Related Disclosures [Abstract]
Net interest income	$ 99,023	111,405
Non-interest revenue	16,679	25,540
Non-interest expense	40,815	33,382
Pre-provision net revenue (PPNR)	74,887	103,563
Balance Sheet Related Disclosures [Abstract]
Loans, net of deferred fees and costs	7,938,581		$ 7,966,794
Total deposits	$ 10,565,568		$ 10,198,357
Total full-time equivalent employees | employee	563		576
Operating Segments | Consumer Banking
Income Statement Related Disclosures [Abstract]
Net interest income	$ 138,627	154,631
Non-interest revenue	17,947	20,728
Non-interest expense	52,358	49,267
Pre-provision net revenue (PPNR)	104,216	126,092
Balance Sheet Related Disclosures [Abstract]
Loans, net of deferred fees and costs	2,781,016		$ 2,825,411
Total deposits	$ 18,921,093		$ 18,698,298
Total full-time equivalent employees | employee	1,510		1,522
Operating Segments | Financial Management Services
Income Statement Related Disclosures [Abstract]
Net interest income	$ 23,220	16,547
Non-interest revenue	46,870	53,206
Non-interest expense	39,948	44,046
Pre-provision net revenue (PPNR)	30,142	25,707
Balance Sheet Related Disclosures [Abstract]
Loans, net of deferred fees and costs	5,349,128		$ 5,374,280
Total deposits	$ 1,633,914		$ 1,488,090
Total full-time equivalent employees | employee	573		604
Treasury and Corporate Other
Income Statement Related Disclosures [Abstract]
Net interest income	$ (25,690)	(932)
Non-interest revenue	26,067	17,752
Non-interest expense	154,891	161,309
Pre-provision net revenue (PPNR)	(154,514)	$ (144,489)
Balance Sheet Related Disclosures [Abstract]
Loans, net of deferred fees and costs	1,757,370		$ 1,731,135
Total deposits	$ 6,263,004		$ 6,506,607
Total full-time equivalent employees | employee	1,755		1,762