Note K - Accounting for Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Note K - Accounting for Stock-based Compensation (Tables) [Line Items]

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

						Aggregate
				Weighted		Intrinsic
				Average		Value
				Exercise		(in
	Shares			Price		thousands)
Outstanding at January 1, 2012		460,653		$	20.50
Exercised		(11,521	)	$	6.73
Granted		203,436		$	25.39
Forfeited/Expired		(13,768	)	$	24.58
Outstanding at December 31, 2012		638,800		$	22.21
Exercised		(159,309	)	$	19.48
Granted		218,707		$	27.03
Forfeited/Expired		(3,646	)	$	24.84
Outstanding at December 31, 2013		694,552		$	24.34
Exercised		(85,063	)	$	21.53
Granted		166,861		$	40.68
Forfeited/Expired		(9,426	)	$	25.53
Outstanding at December 31, 2014		766,924		$	28.20	$	9,804
Vested plus expected to vest at December 31, 2014		749,645		$	28.05	$	9,691
Exercisable at December 31, 2014		393,800		$	23.78	$	6,771

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

			OPTIONS OUTSTANDING						OPTIONS EXERCISABLE
					Weighted
			Number		Average		Weighted		Number		Weighted
			Outstanding		Remaining		Average		Exercisable		Average
Range of			As of		Contractual		Exercise		As of		Exercise
Exercise Prices			12/31/14		Term		Price		12/31/14		Price
$ 9.05	–	$25.00		237,276		5.35	$	22.10		232,242	$	22.10
$25.01	–	$27.00		155,141		7.04	$	25.66		96,885	$	25.66
$27.01	–	$28.00		207,646		8.21	$	27.03		64,673	$	27.03
$28.01	–	$41.00		166,861		9.21	$	40.68		—	$	—
$9.05	to	$41.00		766,924		7.30	$	28.20		393,800	$	23.78

Restricted Stock [Member]

Note K - Accounting for Stock-based Compensation (Tables) [Line Items]

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]

				Weighted-
				Average
				Grant
	Number of			Date Fair
	Shares			Value
Non-vested restricted stock awards at January 1, 2012		34,664		$	24.23
Granted		36,139		$	22.41
Vested		(34,664	)	$	24.23
Non-vested restricted stock awards at December 31, 2012		36,139		$	22.41
Granted		—		$	—
Vested		(30,825	)	$	22.38
Forfeited		(5,314	)	$	22.58
Non-vested restricted stock awards at December 31, 2013		—		$	—

Restricted Stock Units (RSUs) [Member]

Note K - Accounting for Stock-based Compensation (Tables) [Line Items]

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]

				Weighted-
				Average		Aggregate
				Grant		Intrinsic
	Number of			Date Fair		Value
	Shares			Value		(in thousands)
Non-vested RSUs at January 1, 2012		769,019		$	23.67
Granted		374,868		$	25.42
Vested		(230,632	)	$	24.66
Cancelled		(64,664	)	$	24.24
Non-vested RSUs at December 31, 2012		848,591		$	24.32
Granted		229,574		$	27.02
Vested		(288,258	)	$	24.28
Cancelled		(33,719	)	$	24.86
Non-vested RSUs at December 31, 2013		756,188		$	25.13
Granted		265,811		$	39.48
Vested		(333,321	)	$	24.73
Cancelled		(44,791	)	$	27.33
Non-vested RSUs at December 31, 2014		643,887		$	31.10	$	26,386
Restricted stock units expected to vest in the future		604,341		$	31.10	$	24,766

Cash Settled RSUs [Member]

Note K - Accounting for Stock-based Compensation (Tables) [Line Items]

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]

				Weighted-
				Average		Aggregate
				Grant		Intrinsic
				Date Fair		Value
	Shares			Value		(in thousands)
Non-vested CSRSUs at December 31, 2012		—		$	—
Granted		203,115		$	27.84
Cancelled		(2,816	)	$	27.03
Non-vested CSRSUs at December 31, 2013		200,299		$	28.23
Granted		416,432		$	39.12
Vested		(47,742	)	$	27.55
Cancelled		(31,870	)	$	32.12
Non-vested CSRSUs at December 31, 2014		537,119		$	36.36	$	22,011
CSRSUs expected to vest in the future		497,997		$	36.32	$	20,408