Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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No definition available.

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Stock-Based Compensation - Shares of Restricted Stock Granted under 2010 Plan (Details) - Plan 2010 - Restricted Stock - shares	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares	71,374
Remaining Term	2 years
2015 \| Five Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term						5 years
Shares	527
Remaining Term						9 days
2016 \| Five Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term					5 years
Shares	10,874
Remaining Term					24 days
2017 \| Five Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term				5 years
Shares	7,017
Remaining Term				1 year 9 months 18 days
2018 \| Five Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term			5 years
Shares	6,184
Remaining Term			2 years 9 months 18 days
2018 \| Three Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term			3 years
Shares	5,371
Remaining Term			27 days
2018 \| Four Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term			4 years
Shares	2,068
Remaining Term			1 year 9 months 18 days
2019 \| Three Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term		3 years
Shares	16,254
Remaining Term		1 year 9 months 18 days
2019 \| Two Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term		2 years
Shares	1,484
Remaining Term		24 days
2020 \| Three Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term	3 years
Shares	18,592
Remaining Term	2 years 9 months 18 days
2020 \| Two Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term	2 years
Shares	694
Remaining Term	1 year 9 months 18 days
2020 \| One Year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term	1 year
Shares	2,309
Remaining Term	24 days