Acquisitions - Additional Information (Detail) $ / shares in Units, $ in Thousands		3 Months Ended			4 Months Ended	6 Months Ended
	Feb. 28, 2019 $ / shares shares	Jun. 30, 2020 USD ($) $ / shares	Jun. 30, 2019 USD ($) $ / shares	Mar. 31, 2019 $ / shares	Jun. 30, 2019 USD ($) $ / shares	Jun. 30, 2020 USD ($) $ / shares	Jun. 30, 2019 USD ($) $ / shares	Mar. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares
Business Acquisition [Line Items]
Common stock, par value | $ / shares		$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01
Reverse stock split				0.067
Revenue		$ 90,684	$ 155,540			$ 224,108	$ 297,037
Net income from continuing operations		(67,318)	24,807			(56,733)	10,891
Net income from discontinued operations		1,533	(2,705)			9,291	(2,523)
BRMR and Everest Merger Sub Inc. [Member]
Business Acquisition [Line Items]
Common stock, par value | $ / shares	$ 0.01
Net income from continuing operations					$ 19,100
Net income from discontinued operations					2,500
BRMR and Everest Merger Sub Inc. [Member] | Continuing Operations [Member]
Business Acquisition [Line Items]
Revenue					66,500
BRMR and Everest Merger Sub Inc. [Member] | Discontinued Operations [Member]
Business Acquisition [Line Items]
Revenue					$ 3,500
BRMR and Everest Merger Sub Inc. [Member] | General and Administrative Expense [Member]
Business Acquisition [Line Items]
Acquisition costs			$ 3,900			$ 200	$ 18,500
BRMR and Everest Merger Sub Inc. [Member] | Maximum [Member] | General and Administrative Expense [Member]
Business Acquisition [Line Items]
Acquisition costs		$ 100
Common Stock [Member] | BRMR and Everest Merger Sub Inc. [Member]
Business Acquisition [Line Items]
Purchase price paid through shares of common stock | shares	0.29506
Reverse stock split, description	15-to-1
Reverse stock split	0.067