Non-interest Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	$ 19,940	$ 20,118
Fiduciary and asset management fees	13,435	12,151
Card fees	10,199	9,844
Brokerage revenue	8,695	7,226
Insurance revenue	1,213	1,304
Other fees	832	842
Fees and commissions	54,314	51,485
Other revenues	12,732	20,354
Total non-interest income	67,046	71,839
Community Banking
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	5,680	5,771
Fiduciary and asset management fees	0	0
Card fees	205	219
Brokerage revenue	0	0
Insurance revenue	0	0
Other fees	0	0
Fees and commissions	5,885	5,990
Other revenues	2,452	1,648
Total non-interest income	8,337	7,638
Corporate Banking
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	533	459
Fiduciary and asset management fees	0	0
Card fees	0	0
Brokerage revenue	0	0
Insurance revenue	0	0
Other fees	0	0
Fees and commissions	533	459
Other revenues	1,733	1,619
Total non-interest income	2,266	2,078
Retail Banking
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	13,422	13,437
Fiduciary and asset management fees	0	0
Card fees	9,994	9,625
Brokerage revenue	0	0
Insurance revenue	0	0
Other fees	559	574
Fees and commissions	23,975	23,636
Other revenues	1,529	1,566
Total non-interest income	25,504	25,202
Financial Management Services
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	0	0
Fiduciary and asset management fees	13,435	12,151
Card fees	0	0
Brokerage revenue	8,695	7,226
Insurance revenue	1,213	1,304
Other fees	0	0
Fees and commissions	23,343	20,681
Other revenues	5,843	6,597
Total non-interest income	29,186	27,278
Other
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	305	451
Fiduciary and asset management fees	0	0
Card fees	0	0
Brokerage revenue	0	0
Insurance revenue	0	0
Other fees	273	268
Fees and commissions	578	719
Other revenues	1,175	8,924
Total non-interest income	$ 1,753	$ 9,643

Other Fees and Commissions

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- Definition

Amount of commission revenue from buying and selling securities on behalf of customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 05
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=68070981&loc=d3e40544-110947

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(a),(b))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of fees and commissions from financial services and banking activities and correspondent clearing. Includes fees from depositor accounts, credit cards, merchant discounts, and fiduciary and trust activities, guarantee fees, investment advisory, management, and administrative fees, transfer agent fees, and insurance commissions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13)
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Amount of income earned from credit card services (including late, over limit, and annual fees) and debit card services (including interchange fees, annual fees and other fees). Excludes interest income earned on credit card balances and transactions.

+ References

No definition available.

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Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from nontransaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) use of automated teller machines or remote service units; (9) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (10) issuing stop payment orders; (11) certifying checks; and (12) accumulating or disbursing funds deposited in IRAs or Keogh Plan accounts when not handled by the bank's trust department. This item does not include penalties assessed on the early withdrawal of time deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13 (d))
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Income from services rendered by trust departments or by any consolidated subsidiaries acting in a fiduciary capacity, including fees earned for (1) acting as an agent for fiduciary placement and loans and (2) custody or investment advisory services when such fees are not separately billed to the customer. This item excludes commissions and fees received for the accumulation or disbursement of funds deposited to Individual Retirement or Keogh plan accounts when such are not handled by the reporting entity's trust department.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
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- Definition

Revenue from insurance services, including net premiums earned, gain on sale of insurance block, agency management fees and insurance contract fees and commissions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

+ References

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Amount of fee and financial service revenue classified as other.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
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-Paragraph 2
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