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Accounting Policies - Intangible Assets (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Marketing contract
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life (years)	20 years	20 years

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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- Details

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Balance Type:
Period Type: