Note 14 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2013

Income Tax Disclosure [Abstract]

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

	Year ended December 31,
	2013			2012			2011
Income (loss) before income taxes
Domestic	$	33,060,976		$	26,170,313		$	15,962,992
Foreign		(581,445	)		(6,642,892	)		(2,177,978	)
	$	32,479,531		$	19,527,421		$	13,785,014

	Year ended December 31,
	2013			2012			2011
Provision for (benefit from) income taxes:
Current provision:
Federal	$	8,024,303		$	7,594,287		$	3,327,626
State		1,580,963			885,958			155,855
Foreign		94,136			(188,650	)		90,626
		9,699,402			8,291,595			3,574,107
Deferred provision:
Federal		2,374,850			776,486			1,907,408
State		114,546			602,447			570,869
Foreign		(283,788	)		(1,900,567	)		(734,050	)
		2,205,608			(521,634	)		1,744,227
Total provision	$	11,905,010		$	7,769,961		$	5,318,334

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31,
	2013		2012
Deferred tax assets:
Deferred revenue	$	852,207	$	1,988,509
Stock-based compensation expense		1,358,554		1,584,583
Tax credit carry forward		19,967		194,364
Net operating loss carryforward, foreign		2,578,640		2,520,746
Accrued expenses and other		649,402		954,559
Inventory reserve		283,996		405,302
Deferred tax asset	$	5,742,766	$	7,648,063

	December 31,
	2013			2012
Deferred tax liabilities:
Acquisition-related Intangibles	$	(6,056,162	)	$	(6,482,404	)
Depreciation		(6,964,428	)		(6,131,473	)
Deferred tax liability	$	(13,020,590	)	$	(12,613,877	)

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	Year ended December 31,
	2013			2012			2011
Statutory federal income tax rate		35.0	%		35.0	%		34.0	%
State tax expense, net of federal benefit		4.8	%		6.4	%		5.7	%
Permanent items, including nondeductible expenses		(0.2	%)		0.9	%		0.9	%
State investment tax credit		(0.1	%)		(0.2	%)		(0.2	%)
Federal, state and foreign research and development credits		(0.5	%)		(1.2	%)		(0.4	%)
Foreign rate differential		0.1	%		2.5	%		0.9	%
Domestic production deduction		(2.4	%)		(3.6	%)		(2.3	%)
Effective income tax rate		36.7	%		39.8	%		38.6	%

Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]

	Year ended December 31,
	2013			2012			2011
Unrecognized tax benefit, beginning of year	$	56,170		$	56,170		$	37,428
Tax positions related to current year		-			-			38,329
Tax positions related to prior years		-			38,329			(19,587	)
Statute expirations		(56,170	)		(38,329	)		-
Unrecognized tax benefit, end of year	$	-		$	56,170		$	56,170