Fair Value Measurement - Fair Value of Assets (Liabilities) Not Measured at Fair Value In Consolidated Balance Sheet - Additional Information (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Fixed-Rate Long-Term Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long term debt, carrying value	$ 120.0	$ 180.0

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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