An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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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)(i)
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Employee Benefits (Narrative Defined Benefit Plans) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) subsidiary	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Estimated prior service cost to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 0
Estimated net loss to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 1,213
Expected return on plan assets	7.00%
Percentage of investments for long-term growth included in investment strategy	55.00%
Percentage of investments for short-term growth included in investment strategy	45.00%
Discretionary range for pension fund trustee included in investment policy	10.00%
Number of subsidiaries company provides post-retirement healthcare benefits to \| subsidiary	2
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	7.00%	7.00%	7.00%
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated prior service cost to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 0
Estimated net loss to be amortized from other comprehensive income into net periodic benefit cost during 2012	125
Wage Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	900
Salaried Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	$ 900
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income, target allocation percentage	55.00%
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fixed income, target allocation percentage	45.00%
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of pension plans	80.00%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of pension plans	100.00%