Note 10 - Income Taxes (Detail) - Income tax provisions: (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Federal:
Current									$ 17,330	$ 17,314	$ 18,205
Deferred									(590)	435	1,138
Total federal tax provision									16,740	17,749	19,343
State and Local:
Current									5,321	5,470	5,777
Deferred									(214)	250	(9,179)
Total state and local tax provision									5,107	5,720	(3,402)
Total income tax provision	$ 5,782	$ 5,988	$ 5,519	$ 4,558	$ 5,664	$ 6,756	$ 5,991	$ 5,058	$ 21,847	$ 23,469	$ 15,941