Property and equipment (Tables)

9 Months Ended

Sep. 30, 2015

Property and equipment — net consist of the following (dollar amounts in thousands):


	Estimated Useful Life (Years)		September 30, 2015			December 31, 2014
Land		—	$	5,273		$	5,273
Buildings		39-40		54,948			54,948
Building improvements		5-40		131,388			114,131
Machinery and equipment		3-15		102,432			80,919
Furniture, fixtures and office equipment		5-10		5,015			5,015
Computer equipment and software		3		10,242			10,465
Leasehold improvements		4		—			17
Construction in progress				7,461			39,580

				316,759			310,348
Less accumulated depreciation and amortization				(125,351	)		(118,221	)

Property and equipment — net			$	191,408		$	192,127

Depreciation and Amortization Expense Related to Property and Equipment

Depreciation and amortization expense related to property and equipment for the three and nine months ended September 30, 2015 and 2014 was as follows (in thousands):


	Three months ended September 30,				Nine months ended September 30,
	2015		2014		2015		2014
Depreciation and amortization expense	$	3,165	$	2,449	$	8,282	$	4,972