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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended				6 Months Ended
	Jan. 31, 2019	Sep. 07, 2018	Sep. 05, 2018	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)								0
Payroll tax expense								$ 89	$ 0
2014 Restricted Stock Awards \| Former Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited (in shares)			1,382,665
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares unvested (in shares)				976,950				976,950			1,092,450
Vested (in shares)					(79,231.000)
Weighted-average grant date fair value (in dollars per share)				$ 4.55				$ 4.55			$ 4.51
Restricted Stock \| 2014 Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period								10 years
Unamortized compensation expense				$ 500				$ 500
Shares unvested (in shares)				229,500				229,500
Restricted Stock \| 2014 Restricted Stock Awards \| Former Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of forfeitures						$ (2,400)
Restricted Stock \| 2014 Restricted Stock Awards \| Former Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares withheld for tax obligation (in shares)	36,269
Vested (in shares)	115,500
Payroll tax expense					$ 100
Restricted Stock \| 2018 Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares unvested (in shares)				500,000				500,000
Restricted Stock \| 2018 Restricted Stock Awards \| Former Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense				$ 600				$ 600
Shares granted (in shares)			350,000
Shares withheld for tax obligation (in shares)			102,550
Shares unvested (in shares)			247,450
Restricted Stock \| 2018 Restricted Stock Awards \| Former Chief Executive Officer \| Forecast \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares unvested (in shares)										247,450
Restricted Stock \| Modified Restricted Stock Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense				$ 0				$ 0
Stock-based compensation expense, net of forfeitures					$ 100
Vested (in shares)					79,231
Restricted Stock \| 2018 Modified Restricted Stock Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares unvested (in shares)				247,450				247,450
Restricted Stock \| PWSC Restricted Stock Award \| Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense				$ 700				$ 700
Stock-based compensation expense, net of forfeitures				$ 200			$ 300	$ 400	$ 600
Shares granted (in shares)		1,000
Shares unvested (in shares)				875				875
Weighted-average grant date fair value (in dollars per share)				$ 824.47				$ 824.47
Restricted Stock Units (RSUs) \| 2018 Restricted Stock Awards \| Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense				$ 1,800				$ 1,800
Shares granted (in shares)			500,000