Note 8 - Estimated Rate of Increase in Compensation Levels (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Weighted-average assumptions used to determine net periodic benefit cost for the Gray pension plan:
Discount rate	4.00%	4.97%
Expected long-term rate of return on pension plan assets	7.00%	7.00%
Estimated rate of increase in compensation levels	5.63%	5.63%
Weighted-average assumptions used to determine benefit obligations:
Discount rate	4.31%	4.00%
Estimated rate of increase in compensation levels		5.63%

The interest rate used to adjust for the time value of money for the plan.

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Expected rate of compensation increases (for pay-related plans).

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The interest rate used to adjust for the time value of money.

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An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Expected rate of compensation increases (for pay-related plans).

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