Income taxes (Tables)

12 Months Ended

Dec. 31, 2013

Summary of Expense (Benefit) for Income Tax

The expense (benefit) for income taxes for the years ended December 31, was as follows:


	2013		2012			2011
Current tax expense
Federal	$	2,629	$	3,806		$	2,816
State		955		1,053			827

		3,584		4,859			3,643

Deferred tax expense (benefit)
Federal		967		(542	)		(809	)
State		208		(174	)		(61	)

		1,175		(716	)		(870	)

Total tax expense	$	4,759	$	4,143		$	2,773

Summary of Company's Effective Tax Rate on Income From Continuing Operations and Statutory Tax Rate

A reconciliation between the Company’s effective tax rate on income from continuing operations and the statutory tax rate for the years ended December 31, was as follows:


	2013						2012						2011
	Amount			Percent			Amount			Percent			Amount			Percent
Income tax (benefit) expense at federal statutory rate	$	(4,760	)		34.0	%	$	3,687			34.0	%	$	2,324			34.0	%
State income tax, net of federal benefit		848			(6.1	)		581			5.4			506			7.4
Non-deductible transaction expenses		—			—			—			—			259			3.8
Non-deductible private placement warrant expense		9,531			(68.0	)		152			1.4			130			1.9
Domestic production activity		(376	)		2.7			(221	)		(2.0	)		(216	)		(3.1	)
Research tax credits		(1,054	)		7.5			(44	)		(0.4	)		(240	)		(3.5	)
Tax reserve reassessment		570			(4.1	)		—			—			—			—
Other, net		—			—			(12	)		(0.2	)		10			0.1

Income tax expense	$	4,759			(34.0	)%	$	4,143			38.2	%	$	2,773			40.6	%

Summary of Components of Net Deferred Tax Asset or Liability

Components of the deferred income tax assets and liabilities consisted of the following as of December 31:


	2013			2012
Deferred tax assets
Inventory	$	1,630		$	862
Allowances and bad debts		196			184
Accrued warranty		496			276
Accrued wages and benefits		359			331
Stock compensation		490			192
Deferred revenue		—			512
Other		302			54

Total deferred tax assets		3,473			2,411

Deferred tax liabilities
Tax depreciation in excess of book		(966	)		(371	)

Total deferred tax liabilities		(966	)		(371	)

Net deferred tax assets	$	2,507		$	2,040

Schedule of Net Deferred Tax Assets and Liabilities

The Company’s net deferred tax assets and liabilities are presented as follows in the Company’s consolidated balance sheets as of December 31:


	2013			2012
Current deferred tax assets, net	$	2,811		$	2,176
Non-current deferred tax liabilities, net		(304	)		(136	)

Net deferred tax assets	$	2,507		$	2,040

Schedule of Change in Unrecognized Tax Benefits

The change in unrecognized tax benefits for the year ended December 31, 2013 was follows:


Balance at December 31, 2012	$	—
Gross increases — current period tax positions		555

Balance at December 31, 2013	$	555