Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Related Party Transaction [Line Items]
Income tax rate	17.50%	15.30%	17.10%	13.50%
U.S federal satutory tax rate			21.00%
NuDevco Retail Holdings and NuDevco Retail
Related Party Transaction [Line Items]
Deferred tax assets	$ 28.9		$ 28.9
Net deferred tax asset	$ 15.6		$ 15.6

Deferred Tax Assets, Investment Purchase in Affiliate

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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