Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2016

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill by Operating Segment

Goodwill — Goodwill by operating segment as of December 31, 2016 and 2015 and changes for the years then ended are as follows (in thousands):

	Contract		Pressure
	Drilling		Pumping			Total
Balance December 31, 2014	$	86,234	$	124,561		$	210,795
Changes to goodwill	—			(124,561	)		(124,561	)
Balance December 31, 2015		86,234		—			86,234
Changes to goodwill	—			—			—
Balance December 31, 2016	$	86,234	$	—		$	86,234

Gross Carrying Amount and Accumulated Amortization of Customer Relationships

The gross carrying amount and accumulated amortization of the customer relationships as of December 31, 2016 and 2015 are as follows (in thousands):

	2016							2015
	Gross Carrying		Accumulated			Net Carrying		Gross Carrying		Accumulated			Net Carrying
	Amount		Amortization			Amount		Amount		Amortization			Amount
Customer relationships	$	25,500	$	(22,768	)	$	2,732	$	25,500	$	(19,125	)	$	6,375