Income Taxes (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
Jan. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Federal income tax rate (as a percent)				21.00%		35.00%
Provision for income taxes		$ (5,381)	$ (6,708)	$ (1,096)	$ (16,244)
Deferred tax (benefit) provision		1,300	(900)	(14,454)	15
Current tax provision (benefit)		$ 6,700	$ 7,600	(15,600)	$ 16,200
Repayment of debt				$ 50,000
Preferred equity interest financing agreement \| ACM / Our "Former Manager"
Repayment of debt	$ 50,000

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

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