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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

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related 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)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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

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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

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related 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)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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)
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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)
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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No definition available.

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- Definition

Refers the benchmark period for investment performance objective.

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No definition available.

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- Definition

Element represents the maximum equity securities holdings in any one company in percentage according to the established guidelines.

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No definition available.

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- Definition

Element represents the maximum fixed income securities holdings in any single issuer according to the established guildelines.

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- Definition

Element represents the minimum number of individual stocks that must be included in the domestic stock portfolio according to the established guidelines.

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- Definition

Element represents the minimum number of individual stocks that must be included in the international stock portfolio according to the established guidelines.

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- Definition

Element represents the percentage by which the return on plan assets should exceed the annual rate of inflation.

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No definition available.

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Employee Benefit Plans, Weighted-Average Assumptions Used (Details) - Defined Benefit Pension Plans Combined [Member] - Stock	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Weighted-Average Assumptions Used to Determine Benefit Obligations [Abstract]
Discount rate	3.50%	4.00%
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost [Abstract]
Discount rate	4.00%	4.20%	3.80%
Expected long-term return on plan assets	6.75%	6.75%	7.00%
Rate of compensation increase			3.00%
Target Asset Allocations [Abstract]
Percentage by which the return on plan assets should exceed the annual rate of inflation	3.00%
Maximum equity securities holdings in any one company	5.00%
Minimum number of individual stocks that must be included in the domestic stock portfolio	20
Minimum number of individual stocks that must be included in the international stock portfolio	30
Maximum fixed income securities holdings in any single issuer	5.00%
Minimum [Member]
Weighted-Average Assumptions Used to Determine Benefit Obligations [Abstract]
Rate of compensation increase	2.50%	2.50%
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.50%	2.50%
Target Asset Allocations [Abstract]
Investment performance objectives benchmark period	3 years
Maximum equity securities holdings in any one company	20.00%
Maximum [Member]
Weighted-Average Assumptions Used to Determine Benefit Obligations [Abstract]
Rate of compensation increase	3.00%	3.00%
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	3.00%	3.00%
Target Asset Allocations [Abstract]
Investment performance objectives benchmark period	5 years
Maximum equity securities holdings in any one company	25.00%
Equity Securities [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Asset allocation of plan assets	50.00%
Weighted-average target asset allocations	50.00%
Equity Securities [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Asset allocation of plan assets	70.00%
Weighted-average target asset allocations	70.00%
Large Cap [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	60.00%
Large Cap [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	95.00%
Mid Cap [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
Mid Cap [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	25.00%
Small Cap [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
Small Cap [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	10.00%
International Developed Nations [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
International Developed Nations [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	25.00%
International Emerging Nations [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
International Emerging Nations [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	10.00%
Fixed Income Securities [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Asset allocation of plan assets	30.00%
Weighted-average target asset allocations	30.00%
Fixed Income Securities [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Asset allocation of plan assets	50.00%
Weighted-average target asset allocations	50.00%
U.S. Treasuries [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	15.00%
U.S. Treasuries [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	55.00%
Federal Agency Securities [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
Federal Agency Securities [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	22.00%
Corporate Bonds [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
Corporate Bonds [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	40.00%
Mortgage-Backed Securities [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	15.00%
Mortgage-Backed Securities [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	55.00%
International [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
International [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	20.00%
High Yield Bonds [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
High Yield Bonds [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	20.00%
Cash and Cash Equivalents [Member] \| Minimum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	0.00%
Cash and Cash Equivalents [Member] \| Maximum [Member]
Target Asset Allocations [Abstract]
Weighted-average target asset allocations	10.00%