Note 15 - Summary of the Bank's Compliance (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Savings Bank [Member]
Tier I (leverage) capital:
Capital level	$ 522,961	$ 494,690
Capital level	8.89%	8.89%
Requirement to be well capitalized	$ 294,004	$ 278,175
Requirement to be well capitalized	5.00%	5.00%
Excess	$ 228,957	$ 216,515
Excess	3.89%	3.89%
Common Equity Tier I risk-based capital:
Capital level	$ 522,961	$ 494,690
Capital level	12.20%	12.62%
Requirement to be well capitalized	$ 278,653	$ 254,768
Requirement to be well capitalized	6.50%	6.50%
Excess	$ 244,308	$ 239,922
Excess	5.70%	6.12%
Tier 1 risk-based capital:
Capital level	$ 522,961	$ 494,690
Capital level	12.20%	12.62%
Requirement to be well capitalized	$ 342,958	$ 313,560
Requirement to be well capitalized	8.00%	8.00%
Excess	$ 180,003	$ 181,130
Excess	4.20%	4.62%
Total risk-based capital:
Capital level	$ 545,159	$ 516,226
Capital level	12.72%	13.17%
Requirement to be well capitalized	$ 428,697	$ 391,950
Requirement to be well capitalized	10.00%	10.00%
Excess	$ 116,462	$ 124,276
Excess	2.72%	3.17%
Holding Company [Member]
Tier I (leverage) capital:
Capital level	$ 516,551	$ 490,919
Capital level	8.80%	8.84%
Requirement to be well capitalized	$ 293,532	$ 277,611
Requirement to be well capitalized	5.00%	5.00%
Excess	$ 223,019	$ 213,308
Excess	3.80%	3.84%
Common Equity Tier I risk-based capital:
Capital level	$ 490,015	$ 462,883
Capital level	11.45%	11.83%
Requirement to be well capitalized	$ 278,140	$ 254,335
Requirement to be well capitalized	6.50%	6.50%
Excess	$ 211,875	$ 208,548
Excess	4.95%	5.33%
Tier 1 risk-based capital:
Capital level	$ 516,551	$ 490,919
Capital level	12.07%	12.55%
Requirement to be well capitalized	$ 342,326	$ 313,028
Requirement to be well capitalized	8.00%	8.00%
Excess	$ 174,225	$ 177,891
Excess	4.07%	4.55%
Total risk-based capital:
Capital level	$ 538,749	$ 512,454
Capital level	12.59%	13.10%
Requirement to be well capitalized	$ 427,907	$ 391,285
Requirement to be well capitalized	10.00%	10.00%
Excess	$ 110,842	$ 121,169
Excess	2.59%	3.10%

Common Equity Tier I risk-based capital as defined in the regulations.

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The amount by which the company's Common Equity Tier I risk-based capital exceeds the minimum required for capital adequacy purposes.

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Common Equity Tier I risk-based capital excess ratio as defined by regulations.

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Common Equity Tier I risk-based capital ratio as defined by regulations.

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The amount of Common Equity Tier I risk-based capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Common Equity Tier I risk-based capital ratio to be well capitalized as defined by regulations.

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The amount of total capital as defined in the regulations.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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The amount by which the company's Total Capital exceeds the minimum required for capital adequacy purposes.

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The amount of excess Total Capital divided by risk weighted assets which are assets that are weighted for credit risk according to a formula used by the Reserve Bank.

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The amount by which the company's Tier 1 Leverage Capital exceeds the minimum required for capital adequacy purposes.

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The amount of excess Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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The amount by which the company's Tier 1 Risk Based Capital exceeds the minimum required for capital adequacy purposes.

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The amount of excess Tier 1 Risk Based Capital (which consists of the types of financial capital considered the most reliable and liquid, primarily Shareholders' equity. Examples of Tier 1 capital are common stock or unit, preferred stock or unit that is irredeemable and noncumulative, and retained earnings) divided by risk-weighted assets which are assets that are weighted for credit risk according to a formula used by the Reserve Bank.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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