Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Reduction in taxes
Loss Contingencies [Line Items]
Gain related to income tax settlement, net	$ 1.3
Legal fees and other charges related to tax settlement	0.4
Amended Credit Agreement \| Standby Letter of Credit
Loss Contingencies [Line Items]
Gross financial assurances issued and outstanding	$ 5.5	$ 5.0

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

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- 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

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- Definition

Amount of loss contingency liability.

+ References

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