Note 17 - Stockholders' Equity (Details) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 31, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Note 17 - Stockholders' Equity (Details) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ 1,732,086		$ 1,732,086		$ 1,602,888
Increase (Decrease) in Total Equity				$ 129,200
Percentage Change in Total Equity				8.10%
Net Income (Loss) Attributable to Parent		$ 38,483	$ 35,909	$ 119,663	$ 102,252
Treasury Stock, Value, Acquired, Cost Method				50,700
Dividends, Common Stock, Cash				30,700
Asia Bancshares [Member]
Note 17 - Stockholders' Equity (Details) [Line Items]
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 82,857			$ 82,800
Stock Issued During Period, Shares, Acquisitions (in Shares)	2,580
Payments to Acquire Businesses, Gross	$ 57,006