CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]
Balance at Dec. 31, 2011	$ 215,738us-gaap_StockholdersEquity	$ 0	$ 203	$ 149,877	$ 65,658
Balance (in shares) at Dec. 31, 2011			20,405
Increase (Decrease) in Stockholders Equity
Net income	34,262us-gaap_NetIncomeLoss	0	0	0	34,262
Stock issued under compensation plans, net	1,417	0	3	1,414	0
Stock issued under compensation plans, net (in shares)			346
Tax benefit from stock-based awards	419	0	0	419	0
Stock-based compensation expense	2,924	0	0	2,924	0
Shares repurchased	(108)	0	0	(108)	0
Shares repurchased (in shares)			(6)
Stock issued - other	38	0	0	38	0
Stock issued - other (in shares)			2
Balance at Dec. 31, 2012	254,690us-gaap_StockholdersEquity	0	206	154,564	99,920
Balance (in shares) at Dec. 31, 2012			20,747
Increase (Decrease) in Stockholders Equity
Net income	34,759us-gaap_NetIncomeLoss	0	0	0	34,759
Stock issued under compensation plans, net	2,304	0	4	2,300	0
Stock issued under compensation plans, net (in shares)			494
Tax benefit from stock-based awards	1,305	0	0	1,305	0
Stock-based compensation expense	3,519	0	0	3,519	0
Shares repurchased	(542)	0	0	(542)	0
Shares repurchased (in shares)			(21)
Stock issued - other	56	0	0	56	0
Stock issued - other (in shares)			3
Balance at Dec. 31, 2013	296,091us-gaap_StockholdersEquity	0	210	161,202	134,679
Balance (in shares) at Dec. 31, 2013			21,223
Increase (Decrease) in Stockholders Equity
Net income	36,544us-gaap_NetIncomeLoss	0	0	0	36,544
Stock issued under compensation plans, net	1,064	0	3	1,061	0
Stock issued under compensation plans, net (in shares)			253
Tax benefit from stock-based awards	592	0	0	592	0
Stock-based compensation expense	4,671	0	0	4,671	0
Shares repurchased	(16,447)	0	(7)	(16,440)	0
Shares repurchased (in shares)			(686)
Stock issued - other	38	0	0	38	0
Stock issued - other (in shares)			2
Balance at Dec. 31, 2014	$ 322,553us-gaap_StockholdersEquity	$ 0	$ 206	$ 151,124	$ 171,223
Balance (in shares) at Dec. 31, 2014			20,792

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Number of shares issued which are neither cancelled nor held in the treasury.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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