Defined benefit plan actual percentage return on plan assets

No definition available.

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- Definition

Defined Benefit Plan Health Care Cost Rate Change - Actual Value From Previous Time Period

+ References

No definition available.

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- Definition

Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Maximum

+ References

No definition available.

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- Definition

Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate

+ References

No definition available.

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- References

No definition available.

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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

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ 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)(ii)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(01)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

+ Details

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

+ Details

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

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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

+ Details

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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Retirement Plans (Details Textuals) - USD ($)	12 Months Ended
Retirement Plans (Details Textuals) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Retirements Plans [Line Items]
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year	$ 1,900,000
Expected long-term rate of return on plan assets	6.50%	7.00%
Actual return on plan assets percentage	14.60%	6.36%
Total expense related to 401(k)	$ 14,000,000	$ 14,000,000	$ 11,000,000
Pre-65 Health Care Trend Rate [Member]
Retirements Plans [Line Items]
Health care trend rate assumption	7.50%
Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Maximum	0.50%
Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Minimum	0.25%
Ultimate future rate	5.00%
Post-65 Health Care Trend [Member]
Retirements Plans [Line Items]
Health care trend rate assumption	6.50%
Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Maximum	0.50%
Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Minimum	0.25%
Ultimate future rate	5.00%
Defined Benefit Plan Health Care Cost Rate Change	17.00%
Retirement Account Plan
Retirements Plans [Line Items]
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year	$ 75,000
Employer contributions	$ 6,242,000	$ 0
Expected long-term rate of return on plan assets	6.50%	7.00%
Postretirement Plan
Retirements Plans [Line Items]
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year	$ 75,000
Employer contributions	$ 235,000	$ 248,000
Minimum [Member] \| Equity Securities
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	50.00%
Minimum [Member] \| Fixed income securities
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	30.00%
Minimum [Member] \| Cash and Cash Equivalents
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Minimum [Member] \| Alternative Securities
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Maximum [Member] \| Equity Securities
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	70.00%
Maximum [Member] \| Fixed income securities
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	50.00%
Maximum [Member] \| Cash and Cash Equivalents
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10.00%
Maximum [Member] \| Alternative Securities
Retirements Plans [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	15.00%