Stock Incentive Plans (Details 2)	12 Months Ended
Dec. 31, 2018 $ / shares shares
Exercise prices of outstanding options, Number of options outstanding	69,083
Exercise prices of outstanding options, Average remaining contractual life (years)	6 years 10 months 10 days
Exercise prices of outstanding options, Number of options exercisable	47,091
$6.10 - $13.50 [Member]
Exercise prices of outstanding options, Lower range \| $ / shares	$ 6.10
Exercise prices of outstanding options, Upper range \| $ / shares	$ 13.50
Exercise prices of outstanding options, Number of options outstanding	64,027
Exercise prices of outstanding options, Average remaining contractual life (years)	7 years 2 months 16 days
Exercise prices of outstanding options, Number of options exercisable	42,035
$40.10 - $44.10 [Member]
Exercise prices of outstanding options, Lower range \| $ / shares	$ 40.10
Exercise prices of outstanding options, Upper range \| $ / shares	$ 44.1
Exercise prices of outstanding options, Number of options outstanding	4,255
Exercise prices of outstanding options, Average remaining contractual life (years)	2 years 8 months 26 days
Exercise prices of outstanding options, Number of options exercisable	4,255
$77.50 - $121.10 [Member]
Exercise prices of outstanding options, Lower range \| $ / shares	$ 77.50
Exercise prices of outstanding options, Upper range \| $ / shares	$ 121.10
Exercise prices of outstanding options, Number of options outstanding	312
Exercise prices of outstanding options, Average remaining contractual life (years)	10 months 14 days
Exercise prices of outstanding options, Number of options exercisable	312
$194.90 - $226.90 [Member]
Exercise prices of outstanding options, Lower range \| $ / shares	$ 194.90
Exercise prices of outstanding options, Upper range \| $ / shares	$ 226.90
Exercise prices of outstanding options, Number of options outstanding	489
Exercise prices of outstanding options, Average remaining contractual life (years)	1 year 2 months 8 days
Exercise prices of outstanding options, Number of options exercisable	489

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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