Defined benefit plan assets, target allocation period increase (decrease) percentage.

No definition available.

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- Definition

Defined Benefit Plan, Average Service Period

+ References

No definition available.

+ Details

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- Definition

Other Comprehensive (Income) Loss, Supplemental Executive Retirement Plan, Liability Adjustment

+ References

No definition available.

+ Details

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- 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 net periodic benefit cost 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

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost 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)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one 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 (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- References

No definition available.

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- Definition

Amount, before tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

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Retirement Plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Benefit plan adjustments	$ (1,139)	$ 0	$ (1,139)	$ 0
Other Comprehensive (Income) Loss, Supplemental Executive Retirement Plan, Liability Adjustment	$ (487)	$ 0	$ (487)	$ 0
Pension plan
Defined Benefit Plan Disclosure [Line Items]
Service period			5 years
Current investment policy targets:
Current investment policy target percentage of fluctuation			20.00%
Assumptions used in determining periodic pension cost:
Discount rate			3.90%	4.30%
Expected long-term rate of return on plan assets			7.50%	7.50%
Pension plan \| Equities
Current investment policy targets:
Current investment policy target	65.00%		65.00%
Current investment mix	56.00%		56.00%		60.00%
Pension plan \| Equities \| Maximum
Current investment policy targets:
Current investment policy target	78.00%		78.00%
Pension plan \| Equities \| Minimum
Current investment policy targets:
Current investment policy target	52.00%		52.00%
Pension plan \| Treasury/Corporate Notes
Current investment policy targets:
Current investment policy target	25.00%		25.00%
Current investment mix	41.00%		41.00%		29.00%
Pension plan \| Money market funds
Current investment policy targets:
Current investment policy target	10.00%		10.00%
Current investment mix	3.00%		3.00%		11.00%