Revenue from Contracts with Customers Revenue from Contracts with Customers (Schedule of Trust Fees) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Trust Fees [Line Items]
Trust fees	$ 36,062	$ 32,014
Non-interest income	119,690	109,613
Private Client [Member]
Trust Fees [Line Items]
Trust fees	26,868	23,762
Institutional [Member]
Trust Fees [Line Items]
Trust fees	7,411	6,494
Other Trust Fees [Member]
Trust Fees [Line Items]
Trust fees	$ 1,783	$ 1,758

[Line Items] for Disclosure of information of trust fees earned from contracts with customers

No definition available.

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- Definition

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
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13 (a))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

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

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)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Details

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- Details

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- Details

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