Note 1 - Summary of Significant Accounting Policies (Details) - Effect of Accounting Change on Interim Financial Statements: Interim Condensed Consolidated Statement of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other revenues									$ 53,120	$ 55,616	$ 57,753
Net operating revenues	206,796	195,772	192,011	194,378	193,977	189,307	187,668	190,050	788,957	761,002	773,242
Total costs and expenses									(716,876)	(692,766)	(694,391)
Income Before Non-Operating Income	19,819	19,265	17,001	15,996	20,530	16,610	16,390	14,706	72,081	68,236	78,851
Income Tax Provision									(37,563)	(34,181)	(34,394)
Net Income	16,589	19,877	14,342	13,805	15,895	17,196	13,555	12,654	64,613	59,300	64,990
Net Income Available to Common Shareholders	14,421	17,710	12,174	11,637	13,727	15,029	11,387	10,486	55,942	50,629	56,319
Basic Earnings Per Share (in Dollars per share)	$ 1.04	$ 1.28	$ 0.88	$ 0.84	$ 0.99	$ 1.08	$ 0.82	$ 0.76	$ 4.05	$ 3.65	$ 4.09
Diluted Earnings Per Share (in Dollars per share)	$ 0.99	$ 1.19	$ 0.86	$ 0.82	$ 0.95	$ 1.04	$ 0.81	$ 0.75	$ 3.87	$ 3.57	$ 3.96
Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other revenues										55,876	58,048
Net operating revenues										761,262	773,537
Other operating expenses										198,691	(198,439)
Total costs and expenses										(695,227)	(696,191)
Income Before Non-Operating Income										66,035	77,346
Income Before Income Taxes										91,280	97,879
Income Tax Provision										(33,323)	(33,807)
Net Income										57,957	64,072
Net Income Available to Common Shareholders										49,286	55,401
Basic Earnings Per Share (in Dollars per share)										$ 3.56	$ 4.02
Diluted Earnings Per Share (in Dollars per share)										$ 3.49	$ 3.90
Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other revenues										(260)	(295)
Net operating revenues										(260)	(295)
Other operating expenses										2,461	1,800
Total costs and expenses										2,461	1,800
Income Before Non-Operating Income										2,201	1,505
Income Before Income Taxes										2,201	1,505
Income Tax Provision										(858)	(587)
Net Income										1,343	918
Net Income Available to Common Shareholders										1,343	918
Basic Earnings Per Share (in Dollars per share)										$ 0.09	$ 0.07
Diluted Earnings Per Share (in Dollars per share)										$ 0.08	$ 0.06
As Adjusted [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other revenues										55,616	57,753
Net operating revenues										761,002	773,242
Other operating expenses										(196,230)	(196,639)
Total costs and expenses										(692,766)	(694,391)
Income Before Non-Operating Income										68,236	78,851
Income Before Income Taxes										93,481	99,384
Income Tax Provision										(34,181)	(34,394)
Net Income										59,300	64,990
Net Income Available to Common Shareholders										$ 50,629	$ 56,319
Basic Earnings Per Share (in Dollars per share)										$ 3.65	$ 4.09
Diluted Earnings Per Share (in Dollars per share)										$ 3.57	$ 3.96