Pension and Other Postretirement Benefit Plans (Assumptions used to determine the benefit obligation and net periodic benefit cost) (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Swiss Pension Plan
Weighted-average assumptions used to determine benefit obligation:
Discount rate	0.75%	0.75%
Rate of compensation increase	2.00%	2.00%
Weighted-average assumptions used to determine net periodic pension cost:
Discount rate	0.75%	0.75%
Expected long-term return on plan assets	2.50%	3.00%
Rate of compensation increase	2.00%	2.50%
Percentage of the fair value of total plan assets held in each major category of plan assets:
Percentage of the fair value of total plan assets held in each major category of plan assets:	100.00%	100.00%
Swiss Pension Plan \| Equity securities
Percentage of the fair value of total plan assets held in each major category of plan assets:
Percentage of the fair value of total plan assets held in each major category of plan assets:	33.00%	29.00%
Swiss Pension Plan \| Debt securities
Percentage of the fair value of total plan assets held in each major category of plan assets:
Percentage of the fair value of total plan assets held in each major category of plan assets:	21.00%	23.00%
Swiss Pension Plan \| Real estate investment funds
Percentage of the fair value of total plan assets held in each major category of plan assets:
Percentage of the fair value of total plan assets held in each major category of plan assets:	39.00%	43.00%
Swiss Pension Plan \| Other
Percentage of the fair value of total plan assets held in each major category of plan assets:
Percentage of the fair value of total plan assets held in each major category of plan assets:	7.00%	5.00%
Korea Defined Benefit Plan
Weighted-average assumptions used to determine benefit obligation:
Discount rate	2.98%
Rate of compensation increase	6.11%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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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- References

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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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