Summary of Significant Accounting Policies - Costs (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Advertising costs		$ 0.2	$ 0.2	$ 0.5
Capitalized software		1.2	1.7
Amortized expense		1.2	1.3	1.0
Impairment of capitalized software	$ 0.1	$ 0.1
Capitalized software held for internal use
Estimated useful life (in years)		3 years
Impairment of capitalized software		$ 0.1
Shipping and handling costs
Cost of revenues		$ 13.3	$ 12.4	$ 9.5

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of impairment loss from capitalized computer software costs.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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