Retirement Plans - Information about Plan Assets (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target plan asset allocations range, minimum	45.00%
Target plan asset allocations range, maximum	75.00%
Equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target plan asset allocations range, minimum	20.00%
Target plan asset allocations range, maximum	50.00%
Other investments
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target plan asset allocations range, minimum	0.00%
Target plan asset allocations range, maximum	5.00%
United States
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	100.00%	100.00%
United States \| Short-term investments
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	0.00%	1.00%
United States \| Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	54.00%	23.00%
United States \| Equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	45.00%	57.00%
United States \| Other investments \| Absolute return strategy equity funds
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	1.00%	19.00%
United States \| Other investments \| Insurance contracts
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	0.00%	0.00%
International
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	100.00%	100.00%
International \| Short-term investments
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	1.00%	1.00%
International \| Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	14.00%	24.00%
International \| Equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	0.00%	0.00%
International \| Other investments \| Absolute return strategy equity funds
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	0.00%	0.00%
International \| Other investments \| Insurance contracts
Defined Benefit Plan, Information about Plan Assets [Abstract]
Actual plan asset allocations	85.00%	75.00%

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

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&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 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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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=58740216&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=58740216&loc=d3e1928-114920

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