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Note 1 - Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2018
Notes Tables |
Schedule of Estimated Useful Lives of Assets [Table Text Block] |
Type |  | Estimated Useful Life (in years) |
Buildings |  | 15 | to | 45 |
Building improvements |  | 5 | to | 20 |
Furniture, fixtures, and equipment |  | 3 | to | 25 |
Leasehold improvements |  | Shorter of useful lives or the terms of the leases |

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