Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Comprehensive Loss [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2011	$ 25,853us-gaap_StockholdersEquity	$ 1,167	$ 163,747		$ (139,061)
Balance, shares at Dec. 31, 2011		116,703,000
Net proceeds from sale of common stock	4,329	10	4,319
Net proceeds from sale of common stock, shares		1,000,000
Restricted stock issued, net		12	(12)
Restricted stock issued net, shares		1,179,000
Shares repurchased	(2,261)	(4)	(2,257)
Shares repurchased, shares	(357,123)	(357,000)
Exercise of stock options, net	4,672	80	4,592
Exercise of stock options net, shares	8,018,516	8,019,000
Stock issued for services	28		28
Stock issued for services, shares		10,000
Stock-based compensation	7,409		7,409
Net income	11,030us-gaap_NetIncomeLoss				11,030
Balance at Dec. 31, 2012	51,060us-gaap_StockholdersEquity	1,265	177,826		(128,031)
Balance, shares at Dec. 31, 2012		126,554,000
Restricted stock issued, net		10	(10)
Restricted stock issued net, shares		974,000
Shares repurchased	(1,613)	(1)	(1,612)
Shares repurchased, shares	(136,641)	(137,000)
Exercise of stock options, net	1,586	48	1,538
Exercise of stock options net, shares	4,875,500	4,856,000
Stock-based compensation	6,459		6,459
Net income	51,537us-gaap_NetIncomeLoss				51,537
Balance at Dec. 31, 2013	109,029us-gaap_StockholdersEquity	1,322	184,201		(76,494)
Balance, shares at Dec. 31, 2013		132,247,000
Restricted stock issued, net		6	(6)
Restricted stock issued net, shares		613,000
Shares repurchased	(6,531)	(4)	(6,527)
Shares repurchased, shares	(415,834)	(416,000)
Exercise of stock options, net	1,544	26	1,518
Exercise of stock options net, shares	2,514,621	2,515,000
Stock-based compensation	8,137		8,137
Tax benefit from stock option exercised and vested restricted shares	21,893		21,893
Foreign currency translation adjustment	(53)			(53)
Dividends	(10,785)us-gaap_Dividends				(10,785)
Net income	61,051us-gaap_NetIncomeLoss				61,051
Balance at Dec. 31, 2014	$ 184,285us-gaap_StockholdersEquity	$ 1,350	$ 209,216	$ (53)	$ (26,228)
Balance, shares at Dec. 31, 2014		134,959,000

Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 740

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6419406&loc=d3e23524-113945