Fees and Commissions Revenue Fees and Commissions (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Total fees and commissions		$ 158,986	$ 164,354
Fees and commissions revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		158,986
Fees and commission revenue not from contracts with customers	[1]	56,743
Fees and commissions revenue from contracts with customers	[2]	102,243
Brokerage and trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		30,648
Fees and commission revenue not from contracts with customers	[1]	22,362
Fees and commissions revenue from contracts with customers	[2]	8,286
Trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		10,394
Fees and commission revenue not from contracts with customers	[1]	10,394
Fees and commissions revenue from contracts with customers	[2]	0
Customer hedging revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		10,907
Fees and commission revenue not from contracts with customers	[1]	10,907
Fees and commissions revenue from contracts with customers	[2]	0
Retail brokerage revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,754
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	4,754
Investment banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,593
Fees and commission revenue not from contracts with customers	[1]	1,061
Fees and commissions revenue from contracts with customers	[2]	3,532
Transaction card revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		20,990
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	20,990
TransFund EFT network revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		19,171
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	19,171
Merchant services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,819
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	1,819
Fiduciary and asset management revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		41,832
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	41,832
Personal trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		20,100
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	20,100
Corporate trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		5,641
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	5,641
Institutional trust & retirement plan services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		11,450
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	11,450
Investment management services and other [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,641
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	4,641
Deposit service charges and fees [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		27,161
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	27,161
Commercial account service charge revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		11,908
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	11,908
Overdraft fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		8,612
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	8,612
Check card fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,918
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	4,918
Automated service charge and other deposit fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,723
Fees and commission revenue not from contracts with customers	[1]	0
Fees and commissions revenue from contracts with customers	[2]	1,723
Mortgage banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		26,025
Fees and commission revenue not from contracts with customers	[1]	26,025
Fees and commissions revenue from contracts with customers	[2]	0
Mortgage production revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		16,573
Fees and commission revenue not from contracts with customers	[1]	16,573
Fees and commissions revenue from contracts with customers	[2]	0
Mortgage servicing revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		9,452
Fees and commission revenue not from contracts with customers	[1]	9,452
Fees and commissions revenue from contracts with customers	[2]	0
Other revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		12,330
Fees and commission revenue not from contracts with customers	[1]	8,356
Fees and commissions revenue from contracts with customers	[2]	3,974
Operating Segments [Member] | Commercial [Member] | Fees and commissions revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		40,017
Operating Segments [Member] | Commercial [Member] | Brokerage and trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		3,083
Operating Segments [Member] | Commercial [Member] | Trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Customer hedging revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		2,022
Operating Segments [Member] | Commercial [Member] | Retail brokerage revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Investment banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,061
Operating Segments [Member] | Commercial [Member] | Transaction card revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		20,006
Operating Segments [Member] | Commercial [Member] | TransFund EFT network revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		18,202
Operating Segments [Member] | Commercial [Member] | Merchant services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,804
Operating Segments [Member] | Commercial [Member] | Fiduciary and asset management revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Personal trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Corporate trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Institutional trust & retirement plan services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Investment management services and other [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Deposit service charges and fees [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		11,071
Operating Segments [Member] | Commercial [Member] | Commercial account service charge revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		10,944
Operating Segments [Member] | Commercial [Member] | Overdraft fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		90
Operating Segments [Member] | Commercial [Member] | Check card fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Automated service charge and other deposit fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		37
Operating Segments [Member] | Commercial [Member] | Mortgage banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Mortgage production revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Mortgage servicing revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Commercial [Member] | Other revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		5,857
Operating Segments [Member] | Consumer [Member] | Fees and commissions revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		44,964
Operating Segments [Member] | Consumer [Member] | Brokerage and trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Customer hedging revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Retail brokerage revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Investment banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Transaction card revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,002
Operating Segments [Member] | Consumer [Member] | TransFund EFT network revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		987
Operating Segments [Member] | Consumer [Member] | Merchant services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		15
Operating Segments [Member] | Consumer [Member] | Fiduciary and asset management revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Personal trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Corporate trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Institutional trust & retirement plan services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Investment management services and other [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Consumer [Member] | Deposit service charges and fees [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		15,420
Operating Segments [Member] | Consumer [Member] | Commercial account service charge revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		359
Operating Segments [Member] | Consumer [Member] | Overdraft fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		8,484
Operating Segments [Member] | Consumer [Member] | Check card fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,918
Operating Segments [Member] | Consumer [Member] | Automated service charge and other deposit fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,659
Operating Segments [Member] | Consumer [Member] | Mortgage banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		26,479
Operating Segments [Member] | Consumer [Member] | Mortgage production revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		17,027
Operating Segments [Member] | Consumer [Member] | Mortgage servicing revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		9,452
Operating Segments [Member] | Consumer [Member] | Other revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		2,063
Operating Segments [Member] | Wealth Management [Member] | Fees and commissions revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		74,807
Operating Segments [Member] | Wealth Management [Member] | Brokerage and trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		25,743
Operating Segments [Member] | Wealth Management [Member] | Trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		10,394
Operating Segments [Member] | Wealth Management [Member] | Customer hedging revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		6,965
Operating Segments [Member] | Wealth Management [Member] | Retail brokerage revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,852
Operating Segments [Member] | Wealth Management [Member] | Investment banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		3,532
Operating Segments [Member] | Wealth Management [Member] | Transaction card revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(19)
Operating Segments [Member] | Wealth Management [Member] | TransFund EFT network revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(19)
Operating Segments [Member] | Wealth Management [Member] | Merchant services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Wealth Management [Member] | Fiduciary and asset management revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		41,880
Operating Segments [Member] | Wealth Management [Member] | Personal trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		20,100
Operating Segments [Member] | Wealth Management [Member] | Corporate trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		5,641
Operating Segments [Member] | Wealth Management [Member] | Institutional trust & retirement plan services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		11,450
Operating Segments [Member] | Wealth Management [Member] | Investment management services and other [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4,689
Operating Segments [Member] | Wealth Management [Member] | Deposit service charges and fees [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		665
Operating Segments [Member] | Wealth Management [Member] | Commercial account service charge revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		605
Operating Segments [Member] | Wealth Management [Member] | Overdraft fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		34
Operating Segments [Member] | Wealth Management [Member] | Check card fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Wealth Management [Member] | Automated service charge and other deposit fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		26
Operating Segments [Member] | Wealth Management [Member] | Mortgage banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Wealth Management [Member] | Mortgage production revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Wealth Management [Member] | Mortgage servicing revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Operating Segments [Member] | Wealth Management [Member] | Other revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		6,538
Funds Management and Other [Member] | Fees and commissions revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(802)
Funds Management and Other [Member] | Brokerage and trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,822
Funds Management and Other [Member] | Trading revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Customer hedging revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1,920
Funds Management and Other [Member] | Retail brokerage revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(98)
Funds Management and Other [Member] | Investment banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Transaction card revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1
Funds Management and Other [Member] | TransFund EFT network revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1
Funds Management and Other [Member] | Merchant services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Fiduciary and asset management revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(48)
Funds Management and Other [Member] | Personal trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Corporate trust revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Institutional trust & retirement plan services revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Investment management services and other [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(48)
Funds Management and Other [Member] | Deposit service charges and fees [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		5
Funds Management and Other [Member] | Commercial account service charge revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Overdraft fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		4
Funds Management and Other [Member] | Check card fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Automated service charge and other deposit fee revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		1
Funds Management and Other [Member] | Mortgage banking revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(454)
Funds Management and Other [Member] | Mortgage production revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		(454)
Funds Management and Other [Member] | Mortgage servicing revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		0
Funds Management and Other [Member] | Other revenue [Member]
Disaggregation of Revenue [Line Items]
Total fees and commissions		$ (2,128)

[1] Out of scope revenue generally relates to financial instruments or contractual rights and obligations within the scope of other applicable accounting guidance.

[2] In scope revenue represents revenue subject to FASB ASC Topic 606, Revenue from Contracts with Customers.