Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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Business Combinations - Intangible Assets Acquired (Details) - USD ($) $ in Thousands	Apr. 05, 2017	Dec. 31, 2017
Community Education Centers
Business Acquisition [Line Items]
Total acquired intangible assets	$ 76,000	$ 76,000
Facility management contracts
Business Acquisition [Line Items]
Weighted Average Useful Life (years)	17 years 12 months
Facility management contracts \| Community Education Centers
Business Acquisition [Line Items]
Total acquired intangible assets	$ 75,300
Covenants not to compete
Business Acquisition [Line Items]
Weighted Average Useful Life (years)	1 year
Covenants not to compete \| Community Education Centers
Business Acquisition [Line Items]
Total acquired intangible assets	$ 700