Goodwill and intangible assets (Tables)

12 Months Ended

Dec. 31, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets

Intangible assets

The fair values for acquired intangible assets were determined by management relying in part on valuations performed by independent valuation specialists. Acquisition-related intangible assets are amortized over the life of the assets on an accelerated basis that approximates the expected economic benefit of the assets. This assumption results in amortization that is higher in earlier periods of the useful life. To date there has been no impairment of the Company's intangible assets. The estimated useful lives and carrying value of acquired intangible assets are as follows:

		December 31, 2013						December 31, 2012
(in thousands)	Weighted average useful life (years)	Gross carrying amount		Accumulated amortization		Net carrying amount		Gross carrying amount		Accumulated amortization		Net carrying amount
Intangible assets:
Customer relationships	9	$	2,350	$	1,449	$	901	$	2,350	$	1,117	$	1,233
Developed technology	6	$	1,880	$	1,264	$	616	$	1,880	$	896	$	984
Trademarks	7	$	70	$	43	$	27	$	70	$	30	$	40
Non-compete Agreements	2	70		70		—		70		60		10
Total intangible assets, net		$	4,370	$	2,826	$	1,544	$	4,370	$	2,103	$	2,267

Amortization of intangible assets was $0.7 million, $0.9 million and $1.0 million for the years ended December 31, 2013, 2012 and 2011, respectively.

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

Amortization of acquired intangible assets is reflected in the cost of revenues for developed technology and in operating expenses for the other intangibles. The estimated future amortization of acquired intangible assets as of December 31, 2013 was as follows:

(in thousands)	Future amortization
2014	567
2015	389
2016	258
2017	156
2018	106
Thereafter	68
Future amortization expense	$	1,544