Note 7 - Earnings Per Share ("EPS") (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands			3 Months Ended		5 Months Ended		9 Months Ended
	May 08, 2019	May 07, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	May 02, 2019
Stock Repurchase Program, Authorized Amount									$ 50,000
Payments for Repurchase of Common Stock							$ 30,000	$ 30,000
Accelerated Stock Repurchase [Member]
Stock Repurchase Program, Authorized Amount		$ 30,000							30,000
Payments for Repurchase of Common Stock		$ 30,000
Stock Repurchased During Period, Shares	500
Share Price	$ 39.85
Share Repurchased, Pecentage	60.00%
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 12,000		$ 12,000	$ 12,000	$ 12,000
Number of Additional Shares Deliver to Company if ASR Agreement Settled					200
Repurchase from Open Market [Member]
Stock Repurchase Program, Authorized Amount									$ 20,000
Treasury Stock, Shares, Acquired						0
Share-based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			400	900			700	600