Number of clients for concentration risk

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 32
-Paragraph 2A
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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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Segment and Geographic Information - Concentration Risk (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($) client	Jun. 30, 2017 USD ($) client	Jun. 30, 2018 USD ($) segment client	Jun. 30, 2017 USD ($) client	Dec. 31, 2017 USD ($) client
Segment Information
Number of operating segments \| segment			2
Number of reportable segments \| segment			2
Revenue	$ 97,423	$ 64,995	$ 189,711	$ 129,824
Accounts receivable, net	50,031		50,031		$ 14,174
Graduate Program Segment
Segment Information
Revenue	81,209	$ 64,995	161,768	$ 129,824
Accounts receivable, net	34,758		34,758		12,520
Short Course Segment
Segment Information
Revenue	16,214		27,943
Accounts receivable, net	$ 1,277		$ 1,277		$ 988
Customer concentration risk \| Revenue \| Graduate Program Segment
Segment Information
Number of clients who account for more then 10% \| client	3	4	3	4
Percentage of concentration of credit risk	10.00%	10.00%	10.00%	10.00%
Customer concentration risk \| Revenue \| Short Course Segment
Segment Information
Number of clients who account for more then 10% \| client	0		0
Percentage of concentration of credit risk	10.00%		10.00%
Customer concentration risk \| Accounts receivable, net \| Short Course Segment
Segment Information
Accounts receivable, net	$ 0		$ 0
Customer concentration risk \| Revenue Segment \| Short Course Segment
Segment Information
Number of clients who account for more then 10% \| client	3		3
Credit concentration risk \| Accounts receivable, net \| Graduate Program Segment
Segment Information
Number of clients who account for more then 10% \| client			2		2
Percentage of concentration of credit risk			10.00%		10.00%
Credit concentration risk \| Accounts receivable, net \| Short Course Segment
Segment Information
Percentage of concentration of credit risk	10.00%		10.00%
University client A \| Customer concentration risk \| Revenue \| Graduate Program Segment
Segment Information
Revenue	$ 20,400	$ 19,100	$ 41,100	$ 38,800
Percentage of concentration of credit risk	21.00%	29.00%	22.00%	30.00%
University client A \| Customer concentration risk \| Revenue \| Short Course Segment
Segment Information
Percentage of concentration of credit risk	14.00%		12.00%
University client A \| Customer concentration risk \| Revenue Segment \| Short Course Segment
Segment Information
Percentage of concentration of credit risk	83.00%		83.00%
University client A \| Credit concentration risk \| Accounts receivable, net \| Graduate Program Segment
Segment Information
Accounts receivable, net	$ 26,500		$ 26,500		$ 9,400
Percentage of concentration of credit risk			53.00%		67.00%
University client B \| Customer concentration risk \| Revenue \| Graduate Program Segment
Segment Information
Revenue	$ 13,100	$ 12,100	$ 26,500	$ 23,800
Percentage of concentration of credit risk	13.00%	19.00%	14.00%	18.00%
University client B \| Credit concentration risk \| Accounts receivable, net \| Graduate Program Segment
Segment Information
Accounts receivable, net	$ 7,500		$ 7,500		$ 2,000
Percentage of concentration of credit risk			15.00%		14.00%
University client C \| Customer concentration risk \| Revenue \| Graduate Program Segment
Segment Information
Revenue	$ 10,200	$ 6,900	$ 19,800	$ 13,800
Percentage of concentration of credit risk	10.00%	11.00%	10.00%	11.00%
University client D \| Customer concentration risk \| Revenue \| Graduate Program Segment
Segment Information
Revenue		$ 6,800		$ 13,200
Percentage of concentration of credit risk		10.00%		10.00%