Note 1 - Basis of Presentation - Reconciliation of Basic to Diluted Weighted-average Shares Outstanding (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Weighted-average shares outstanding-basic (in shares)	71,821	71,878	71,849	71,835
Common stock equivalents for stock options and restricted shares (in shares)	680	870	661	830
Weighted-average shares outstanding-diluted (in shares)	72,501	72,748	72,510	72,665