Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Publisher FASB
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SIGNIFICANT ACCOUNTING POLICIES - Stock-Based Compensation (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0	0	0	0
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			3 years
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			6 years
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for award (in shares)	1,585,000		1,585,000
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for award (in shares)	1,789,647		1,789,647