Note 17 - Concentration of Third-party Mortgage Purchasers - Percent of Mortgage Loans Sold to Third-party Purchasers (Details) - Customer Concentration Risk [Member]	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Wells Fargo Funding, Inc. [Member]
Percentage of mortgage loans sold to third-party purchasers	26.00%	10.00%	37.00%
PennyMac Loan Services, LLC [Member]
Percentage of mortgage loans sold to third-party purchasers	15.00%	14.00%	23.00%
Fannie Mae [Member]
Percentage of mortgage loans sold to third-party purchasers	10.00%	7.00%	10.00%
JPMorgan Chase Bank, N.A. [Member]
Percentage of mortgage loans sold to third-party purchasers	8.00%	32.00%	20.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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