Amount of noncash expense for share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

+ References

No definition available.

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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

Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

+ References

No definition available.

+ Details

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STOCK-BASED COMPENSATION - Modified Vesting of Shares (Details) - USD ($) $ in Thousands	6 Months Ended		9 Months Ended	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2018
Stock-based compensation
Stock-based compensation	$ 36,309	$ 28,056
Non-cash stock-based compensation expense			$ 3,900
Former Chief Operating Officer
Stock-based compensation
Accelerated vesting, shares				69,950
Former Chief Operating Officer \| Restricted Shares and RSUs
Stock-based compensation
Accelerated vesting, shares				54,350