The amount of expense, net of income tax, on a per basic and diluted share basis, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

No definition available.

Note 9 - Employee Benefits (Detail) (USD $)	12 Months Ended							1 Months Ended			12 Months Ended		12 Months Ended			12 Months Ended								12 Months Ended
Note 9 - Employee Benefits (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Stock Options [Member] 2005 Plan [Member]	Dec. 31, 2012 Stock Options [Member] 1995 Plan [Member]	Dec. 31, 2012 Stock Options [Member]	Dec. 31, 2012 Performance Shares [Member] 2005 Plan [Member]	May 31, 2012 Performance Shares [Member]	Aug. 30, 2011 Performance Shares [Member]	Aug. 30, 2010 Performance Shares [Member]	Dec. 31, 2012 Performance Shares [Member]	Dec. 31, 2012 Non-Statutory Stock Options [Member] 1995 Plan [Member]	Dec. 31, 2010 Performance-Based Option Awards [Member]	Dec. 31, 2012 Unvested Service-Based Option Awards [Member]	Dec. 31, 2012 Unvested Performance Unit Awards [Member]	Dec. 31, 2012 Service-Based Options [Member]	Dec. 31, 2011 Service-Based Options [Member]	Dec. 31, 2010 Service-Based Options [Member]	Dec. 31, 2012 Participants Less Than 50 Years Old [Member]	Dec. 31, 2012 Participants Over 50 Years Old [Member]	Dec. 31, 2012 2005 Plan [Member] Minimum [Member]	Dec. 31, 2012 2005 Plan [Member] Maximum [Member]	Dec. 31, 2012 2005 Plan [Member]	Dec. 31, 2012 1995 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expiration Term																					7 years	10 years		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				1 year		1 year	5 years			5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Annual Percentage of Award Which Vests				20.00%	20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)																							2,850,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Reserved For Issuance Under Awards Outstanding (in Shares)				638,050	25,314		122,083
Share-Based Compensation Award, Exercise Price, Required Percentage of Fair Market Value of Common Stock On the Date of Grant												85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period (in Shares)													107,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted (in Shares)								39,500	41,600	63,400
Share-based Compensation Arrangement by Share-Based Payment Awards, Annual Service Vesting Percentage										5.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Forfeiture Rate of Unvested Outstanding Awards	1.25%
Allocated Share-based Compensation Expense	$ 1,225,000	$ 1,349,000	$ 1,264,000
Allocated Share-based Compensation Expense, Net of Tax	759,000	837,000	776,000
Allocated Share-based Compensation Expense, Net of Tax, Amount Per Basic And Diluted Share (in Dollars per share)	$ 0.034	$ 0.038	$ 0.035
Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Financing Activities	336,000	142,000	338,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized														1,300,000	1,300,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	3 years 36 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number (in Shares)	663,364	690,768
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	4 years 36 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	552,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number (in Shares)	465,144
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	3 years 255 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	513,000
Stock Granted During Period, Value, Share-based Compensation, Gross																695,000	350,000	922,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	1,400,000	442,000	1,000,000
Proceeds from Stock Options Exercised	968,000	137,000	303,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	751,000	856,000	729,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value											468,000
Defined Contribution Plan, Maximum Statutory Contribution Amount Allowed By Each Plan Participant																			17,000	22,500
Defined Contribution Plan, Percentage of Participant's Contribution Matched By Employer	35.00%
Defined Contribution Plan, Max Percentage of Participant's Contributions Matched By Employer	6.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	20.00%
Defined Contribution Plan, Cost Recognized	$ 909,000	$ 803,000	$ 633,000