Loans and Leases and the Allowance for Credit Losses - Schedule of Recorded Investment in Loans and Leases by Class and Credit Quality Indicator (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	$ 11,940,020	$ 10,990,892
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	5,100,686	4,213,827
Commercial | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	1,875,293	1,379,152
Commercial | Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	2,854,829	2,518,051
Commercial | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	259,798	194,170
Commercial | Lease Financing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	110,766	122,454
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	6,839,334	6,777,065
Consumer | Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	395,483	489,606
Consumer | Residential Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	4,130,513	3,891,100
Consumer | Home Equity
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	1,604,538	1,676,073
Consumer | Automobile
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases	$ 708,800	720,286
Pass | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		4,079,663
Pass | Commercial | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		1,306,040
Pass | Commercial | Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		2,463,858
Pass | Commercial | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		188,832
Pass | Commercial | Lease Financing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		120,933
Pass | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		6,765,307
Pass | Consumer | Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		488,113
Pass | Consumer | Residential Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		3,886,389
Pass | Consumer | Home Equity
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		1,671,468
Pass | Consumer | Automobile
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		719,337
Special Mention | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		58,323
Special Mention | Commercial | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		37,722
Special Mention | Commercial | Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		16,453
Special Mention | Commercial | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		4,148
Classified | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		75,841
Classified | Commercial | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		35,390
Classified | Commercial | Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		37,740
Classified | Commercial | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		1,190
Classified | Commercial | Lease Financing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		1,521
Classified | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		11,758
Classified | Consumer | Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		1,493
Classified | Consumer | Residential Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		4,711
Classified | Consumer | Home Equity
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		4,605
Classified | Consumer | Automobile
Financing Receivable, Credit Quality Indicator [Line Items]
Total Recorded Investment in Loans and Leases		$ 949