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Leases (Supplemental Lease Information) (Details)	Mar. 31, 2019
Supplemental Lease Information [Line Items]
Weighted average remaining lease term, operating leases	5 years
Weighted average remaining lease term, finance leases	1 year
Weighted average discount rate, operating leases	3.30%
Weighted average discount rate, finance leases	0.00%	[1]
[1] Prior to adoption of ASU 2016-02, our historical capital lease liability and asset were measured using an un-discounted cash flow stream due to immateriality of the capital lease population. As we have elected the practical expedient that does not require us to reassess our population of capital leases upon adoption of ASU 2016-02, our existing finance leases do not have a weighted-average discount rate.

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- Definition

[Line Items] for Supplemental information about operating and finance leases, including weighted average remaining lease term and weighted average discount rates.

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Weighted average discount rate for finance lease calculated at point in time.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(4)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(4)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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