Employee Benefit Plans (Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($) shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock options available to be awarded (in shares)	536,000
Anticipated contribution to benefit plan \| $	$ 1.6
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%
Median return on average assets of all FDIC insured depository institutions time period	20 years
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

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

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
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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

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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

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-Publisher FASB
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-Topic 718
-SubTopic 10
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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

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-Publisher FASB
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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

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- Definition

Percentage of vesting of share-based compensation awards.

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