Note 19 - Fair Value Disclosures (Details Textual) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Payments to Acquire Available-for-sale Securities | $ 351,644 | $ 259,676 | $ 231,324 |
| Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | |||
| Assets, Fair Value Disclosure | 0 | 0 | |
| Payments to Acquire Available-for-sale Securities | $ 0 | $ 0 | |