Consolidated Statements of Stockholders’ Equity (USD $)	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Translation Adjustment [Member]	Total
Balance at Dec. 31, 2011	$ 136,305	$ 63,441,433	$ 34,252,221	$ (3,067,181)	$ 94,762,778
Balance (in Shares) at Dec. 31, 2011	13,630,607
Issuance of common stock for employee equity awards	2,354	386,321			388,675
Issuance of common stock for employee equity awards (in Shares)	235,453
Tax benefit related to stock based compensation		452,471			452,471
Stock based compensation expense		1,151,199			1,151,199
Net income			11,757,460		11,757,460
Other comprehensive income (loss)				412,551	412,551
Balance at Dec. 31, 2012	138,659	65,431,424	46,009,681	(2,654,630)	108,925,134
Balance (in Shares) at Dec. 31, 2012	13,866,060
Issuance of common stock for employee equity awards	4,234	3,049,707			3,053,941
Issuance of common stock for employee equity awards (in Shares)	423,248
Tax benefit related to stock based compensation		856,830			856,830
Stock based compensation expense		1,268,070			1,268,070
Net income			20,574,521		20,574,521
Other comprehensive income (loss)				955,535	955,535
Balance at Dec. 31, 2013	142,893	70,606,031	66,584,202	(1,699,095)	135,634,031
Balance (in Shares) at Dec. 31, 2013	14,289,308
Issuance of common stock for employee equity awards	6,961	2,047,745			2,054,706
Issuance of common stock for employee equity awards (in Shares)	696,169
Tax benefit related to stock based compensation		9,626,064			9,626,064
Stock based compensation expense		1,607,421			1,607,421
Retirement of common stock for minimum tax withholdings	(1,337)	(6,347,562)			(6,348,899)
Retirement of common stock for minimum tax withholdings (in Shares)	(133,774)
Net income			38,319,479		38,319,479
Other comprehensive income (loss)				(2,795,705)	(2,795,705)
Balance at Dec. 31, 2014	$ 148,517	$ 77,539,699	$ 104,903,681	$ (4,494,800)	$ 178,097,097
Balance (in Shares) at Dec. 31, 2014	14,851,703