Note 19 - Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2015

Notes Tables

Schedule of Quarterly Financial Information [Table Text Block]

20 15 Quarters (In thousands, except per share amounts)	First		Second		Third		Fourth
Operating revenue	$	161,287	$	163,588	$	171,346	$	168,773
Operating income		17,311		14,161		14,354		15,237
Net income		10,188		8,357		8,410		8,790
Basic earnings per common share		0.30		0.25		0.25		0.26
Diluted earnings per common share		0.30		0.25		0.25		0.26

2014 Quarters ( In thousands, except per share amounts)	First		Second		Third		Fourth
Operating revenue	$	159,409	$	168,423	$	171,550	$	173,547
Operating income		8,640		12,932		13,042		16,392
Net income		5,287		7,926		7,652		8,969
Basic earnings per common share		0.16		0.24		0.23		0.27
Diluted earnings per common share		0.16		0.24		0.23		0.27