Defined Benefit Plan, Annual Vesting Percentage

No definition available.

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- Definition

Defined Benefit Plan, Benefit Obligation, Percent Of Average Executive Base Salary

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Benefit Obligation, Percent Of Average Executive Base Salary, Adjustment Thereafter

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Number of Annual Payments After Separation

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Payment Term After Separation

+ References

No definition available.

+ Details

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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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.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ 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=96867065&loc=d3e5070-113901

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Employee Benefit Plans (SERP Narrative) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) payment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation		$ 1,187	$ 1,023	$ 923
President and CEO \| SERP
Defined Benefit Plan Disclosure [Line Items]
Percent of average executive base salary	40.00%
Payment term after separation	36 months
Percent of average executive base salary, adjustment thereafter	2.00%
Number of annual payments after separation \| payment	15
Benefit obligation	$ 3,400
Assumptions used calculating benefit obligation, discount rate	4.00%
Annual vesting percentage	3.00%
Award vesting rights, percentage	100.00%