Share-Based Compensation (Details) $ / shares in Units, $ in Thousands		7 Months Ended	12 Months Ended
		Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) Plan Period $ / shares shares		Dec. 31, 2017 USD ($)	Jun. 30, 2018 shares
Share-based Compensation expenses [Abstract]
Share-based compensation | $			$ 29,940		$ 0
Performance Unit and Option Awards [Abstract]
Common stock, shares outstanding (in shares) | shares		24,957,309	24,957,309
Valuation Assumptions for Determination of Fair Value [Abstract]
Shares available for grant (in shares) | shares		2,900,000	2,900,000
Additional Disclosures [Abstract]
Share price (in dollars per share)		$ 15.00	$ 15.00
Manufacturing and Supply [Member]
Share-based Compensation expenses [Abstract]
Share-based compensation | $			$ 414
Research and Development [Member]
Share-based Compensation expenses [Abstract]
Share-based compensation | $			2,583
Selling, General and Administrative [Member]
Share-based Compensation expenses [Abstract]
Share-based compensation | $			$ 26,943
Discount for Lack of Marketability [Member]
Valuation Assumptions for Determination of Fair Value [Abstract]
Valuation assumptions		0.34	0.34
Volatility [Member]
Valuation Assumptions for Determination of Fair Value [Abstract]
Valuation assumptions		0.9	0.9
Weighted Average Cost of Capital [Member]
Valuation Assumptions for Determination of Fair Value [Abstract]
Valuation assumptions		0.275	0.275
Nonvoting Common Stock [Member]
Share-based Compensation expenses [Abstract]
Share-based compensation | $	[1]		$ 27,298
Performance Unit and Option Awards [Abstract]
Common stock, shares outstanding (in shares) | shares		4,922,353	4,922,353			4,922,353
Fair market value of non-voting shares at shares granted date | $			$ 19,123
Withholding taxes on share-based compensation | $			$ 8,175
Number of common shares issued (in shares) | shares			4,922,353
Performance Units [Member]
Performance Unit and Option Awards [Abstract]
Number of performance units plans | Plan			2
Restricted Stock Units [Member]
Share-based Compensation expenses [Abstract]
Share-based compensation | $		$ 1,085	$ 1,085	[2]
Performance Unit and Option Awards [Abstract]
Service period			2 years
Number of Units [Roll Forward]
Unvested at Plan adoption (in shares) | shares		0
Granted (in shares) | shares		265,000
Vested (in shares) | shares		(60,000)
Unvested, at end of period (in shares) | shares		205,000	205,000
Weighted Average Grant Date Fair Value Per Share [Abstract]
Unvested at Plan adoption (in dollars per share)		$ 0
Granted (in dollars per share)		14.83
Vested (in dollars per share)		15.03
Unvested, Balance at end of period (in dollars per share)		$ 14.77	$ 14.77
Additional Disclosures [Abstract]
Grant date fair value | $		$ 896	$ 896
Compensation Cost Not yet Recognized [Abstract]
Unrecognized stock-based compensation expense | $		$ 2,568	$ 2,568
Unrecognized compensation cost, recognition period			3 years
Weighted average grant date fair value (in dollars per share)		$ 14.83
Restricted Stock Units [Member] | Senior Management and Board [Member]
Additional Disclosures [Abstract]
Vesting period			2 years
Restricted Stock Units [Member] | key Employees [Member]
Additional Disclosures [Abstract]
Vesting period			3 years
Stock Options [Member]
Share-based Compensation expenses [Abstract]
Share-based compensation | $	[2]		$ 1,557
Performance Unit and Option Awards [Abstract]
Service period			3 years
Weighted Average Grant Date Fair Value Per Share [Abstract]
Granted (in dollars per share)			$ 10.83
Number of Options [Roll Forward]
Outstanding at beginning of period (in shares) | shares		0
Granted (in shares) | shares		1,033,000
Exercised, Forfeited, Expired (in shares) | shares		0
Outstanding at end of period (in shares) | shares		1,033,000	1,033,000
Vested or expected to vest at end of period (in shares) | shares		962,000	962,000
Exercisable at end of period (in shares) | shares		87,000	87,000
Weighted Average Exercise Price [Abstract]
Granted (in dollars per share)		$ 14.72
Outstanding at end of period (In dollars per share)		14.72	$ 14.72
Vested or expected to vest at end of period (in dollars per share)		14.72	14.72
Exercisable at end of period (in dollars per share)		$ 15.02	$ 15.02
Weighted Average Remaining Contractual Term in Years [Abstract]
Granted		9 years 6 months 18 days
Outstanding at end of period			9 years 6 months 18 days
Vested or expected to vest at end of period			9 years 6 months 18 days
Exercisable at end of period			9 years 6 months 22 days
Aggregate Intrinsic Value [Abstract]
Granted | $		$ 0
Outstanding at end of period | $		0	$ 0
Vested or expected to vest at end of period | $		0	0
Exercisable at end of period | $		$ 0	$ 0
Additional Disclosures [Abstract]
Stock options grant, exercise price (in dollars per share)		$ 14.72
Term of award			10 years
Share price (in dollars per share)		$ 6.30	$ 6.30
Number of vesting periods | Period			2
Fair Value Assumptions [Abstract]
Expected dividend yield			0.00%
Expected volatility			90.00%
Compensation Cost Not yet Recognized [Abstract]
Unrecognized stock-based compensation expense | $		$ 8,845	$ 8,845
Unrecognized compensation cost, recognition period			2 years 7 months 6 days
Weighted average grant date fair value (in dollars per share)			$ 10.83
Stock Options [Member] | Minimum [Member]
Weighted Average Exercise Price [Abstract]
Granted (in dollars per share)			6.54
Additional Disclosures [Abstract]
Stock options grant, exercise price (in dollars per share)			$ 6.54
Fair Value Assumptions [Abstract]
Expected term (years)			5 years 9 months 18 days
Risk-free rate			2.80%
Stock Options [Member] | Maximum [Member]
Weighted Average Exercise Price [Abstract]
Granted (in dollars per share)			$ 18.67
Additional Disclosures [Abstract]
Stock options grant, exercise price (in dollars per share)			$ 18.67
Fair Value Assumptions [Abstract]
Expected term (years)			6 years 1 month 6 days
Risk-free rate			2.90%
Stock Options [Member] | Senior Management and Board [Member]
Additional Disclosures [Abstract]
Vesting period			3 years
Stock Options [Member] | key Employees [Member]
Additional Disclosures [Abstract]
Vesting period			3 years
Employee Stock Purchase Plan [Member]
Employee Stock Purchase Plan [Abstract]
Number of shares reserved for issuance (in shares) | shares			250,000
Purchase price of common stock as percentage of fair market value			85.00%

[1] Non-Voting Common Share Issuance

[2] Share-Based Compensation Equity Awards