Business Combinations - Useful Lives of Acquired Assets (Details) - Grovo Learning, Inc.	Nov. 09, 2018
Business Acquisition [Line Items]
Useful life of property	25 years
Content Library
Business Acquisition [Line Items]
Useful life of intangible asset	6 years
Developed Technology
Business Acquisition [Line Items]
Useful life of intangible asset	3 years

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration