Note 6 - Fair Value Measurements (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings, Total	$ 0	$ 0	$ 0	$ 200,000
Minimum [Member]
Short Term Borrowings Maturity Period			30 days
Financial Services Segment [Member]
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings, Total		29,000		160,000
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage	114,836,000		114,836,000		$ 138,114,000
Gain (Loss) on Sale of Mortgage Loans	11,800,000	$ 9,800,000	31,100,000	$ 28,500,000
Fair Value, Inputs, Level 2 [Member] \| Under Commitment to Sell [Member]
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage	101,700,000		101,700,000		103,500,000
Fair Value, Inputs, Level 2 [Member] \| Not Under Commitment to Sell [Member]
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage	$ 13,100,000		$ 13,100,000		$ 34,600,000

Number of days from date of origination to date of sale of loan.

No definition available.

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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

+ Details

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- Definition

Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

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