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.

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Summary of Significant Accounting Policies - New Accounting Pronouncements (Details) - USD ($) $ in Millions	Jan. 01, 2019	Jan. 01, 2018
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect transition adjustment resulting from earlier recognition of revenue		$ (2.3)
Subsequent Event \| Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect transition adjustment resulting from earlier recognition of revenue	$ 9.4
Subsequent Event \| Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use asset	4.7
Lease liability	4.7
Amberjack Pipeline Company LLC ("Amberjack") \| Subsequent Event \| Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect transition adjustment resulting from earlier recognition of revenue	$ 18.9