Summary of Significant Accounting Policies, Credit Loss Adoption Impact (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			$ 201,371
Cumulative effect of ASU 2016-13 adoption (CECL)	$ 47,776		21,907
Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			166,846
Cumulative effect of ASU 2016-13 adoption (CECL)			20,465
Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			34,525
Cumulative effect of ASU 2016-13 adoption (CECL)			1,443
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Commercial and industrial | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			91,133
Cumulative effect of ASU 2016-13 adoption (CECL)			12,276
Commercial real estate - owner occupied | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			10,284
Cumulative effect of ASU 2016-13 adoption (CECL)			127
Commercial and business lending | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			101,417
Cumulative effect of ASU 2016-13 adoption (CECL)			12,403
Commercial real estate - investor | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			40,514
Cumulative effect of ASU 2016-13 adoption (CECL)			530
Real estate construction | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			24,915
Cumulative effect of ASU 2016-13 adoption (CECL)			7,532
Commercial Real Estate | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			65,428
Cumulative effect of ASU 2016-13 adoption (CECL)			8,062
Residential mortgage | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			16,960
Cumulative effect of ASU 2016-13 adoption (CECL)			0
Home Equity Loan | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			10,926
Cumulative effect of ASU 2016-13 adoption (CECL)			1,038
Other consumer | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss			6,639
Cumulative effect of ASU 2016-13 adoption (CECL)			$ 405
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Maximum
Finite-Lived Intangible Assets [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%
Cumulative Effect, Period of Adoption, Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		$ 131,147
Cumulative Effect, Period of Adoption, Adjustment [Member] | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		75,171
Cumulative Effect, Period of Adoption, Adjustment [Member] | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		55,975
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial and industrial | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		48,921
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial real estate - owner occupied | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		(1,851)
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial and business lending | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		47,070
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial real estate - investor | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		2,287
Cumulative Effect, Period of Adoption, Adjustment [Member] | Real estate construction | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		25,814
Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Real Estate | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		28,101
Cumulative Effect, Period of Adoption, Adjustment [Member] | Residential mortgage | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		33,215
Cumulative Effect, Period of Adoption, Adjustment [Member] | Home Equity Loan | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		14,240
Cumulative Effect, Period of Adoption, Adjustment [Member] | Other consumer | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		8,520
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		354,425
Cumulative effect of ASU 2016-13 adoption (CECL)		40,597
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		262,482
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		91,943
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commercial and industrial | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		152,330
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commercial real estate - owner occupied | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		8,560
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commercial and business lending | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		160,890
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commercial real estate - investor | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		43,331
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Real estate construction | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		58,261
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commercial Real Estate | Total commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		101,591
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Residential mortgage | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		50,175
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Home Equity Loan | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		26,204
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Other consumer | Total consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		$ 15,564