Income Taxes - Narrative (Details)	4 Months Ended
	Dec. 31, 2017 USD ($)
Tax Credit Carryforward [Line Items]
Deferred tax assets before valuation allowance	$ 63,971,000
Recognized net tax benefit	(4,799,000)
Reclassification of debt to equity, tax effect	17,044,000
Undistributed earnings of foreign subsidiaries	0
Domestic
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	162,523,000
Tax credit carryforwards	2,010,000
Foreign
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	37,335,000
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	207,131,000
Tax credit carryforwards	546,000
Additional Paid-in Capital
Tax Credit Carryforward [Line Items]
Reclassification of debt to equity, tax effect	$ 17,044,000