Employee Benefit Plans (Narrative) (Details)	9 Months Ended
Sep. 30, 2017 shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock options available to be awarded (in shares)	560,000
Employee Stock Option
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Incentive stock options and SARs exercisable period	10 years
Performance Shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Award vesting rights percentage	33.33%
Maximum
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Common stock issued upon the exercise of stock options, SARs and stock awards (in shares)	750,000
Share-based Compensation Award, Tranche One \| Performance Shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Median return on average assets of all FDIC insured depository institutions time period	20 years
Share-based Compensation Award, Tranche Two \| Performance Shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Median return on average assets of all FDIC insured depository institutions time period	20 years
Share-based Compensation Award, Tranche Three \| Performance Shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Median return on average assets of all FDIC insured depository institutions time period	20 years

Median Return on Average Assets of all FDIC Insured Depository Institutions Time Period

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- Definition

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.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Percentage of vesting of share-based compensation awards.

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