Commitments and Contingencies Purchase obligations (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2019	Mar. 31, 2019
Long-term Purchase Commitment [Line Items]
Outstanding purchase commitments		$ 2.5
Scenario, Forecast
Long-term Purchase Commitment [Line Items]
Purchase commitment	$ 1.9

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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