Summary of Business and Significant Accounting Policies, Goodwill Impairment Assessments (Details) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) Reportingunit
Goodwill Impairment Assessment [Abstract]
Number of reporting unit \| Reportingunit		1
Impairment of goodwill \| $	$ 14,740	$ 0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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