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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
Customer Relationships [Member] |  |  |
Finite-Lived Intangible Assets, Net | $ 7,166,000 | $ 11,698,000 |
Finite-Lived Intangible Assets, Accumulated Amortization | 14,938,000 | 10,406,000 |
Developed Technology Rights [Member] |  |  |
Finite-Lived Intangible Assets, Net | 787,000 | 1,292,000 |
Finite-Lived Intangible Assets, Accumulated Amortization | 1,738,000 | $ 1,233,000 |
Prepaid Expenses and Other Current Assets [Member] | New Dawn [Member] |  |  |
Deferred Set-up Costs, Current | $ 350,000 |  |
Minimum [Member] | Building and Building Improvements [Member] |  |  |
Property, Plant and Equipment, Useful Life | 5 years |  |
Minimum [Member] | Furniture, Office Equipment, and Software [Member] |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Minimum [Member] | Machinery and Equipment [Member] |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Minimum [Member] |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Maximum [Member] | Building and Building Improvements [Member] |  |  |
Property, Plant and Equipment, Useful Life | 39 years |  |
Maximum [Member] | Furniture, Office Equipment, and Software [Member] |  |  |
Property, Plant and Equipment, Useful Life | 5 years |  |
Maximum [Member] | Machinery and Equipment [Member] |  |  |
Property, Plant and Equipment, Useful Life | 10 years |  |
Maximum [Member] |  |  |
Property, Plant and Equipment, Useful Life | 39 years |  |
Product Concentration Risk [Member] | Sales Revenue, Net [Member] |  |  |
Concentration Risk, Percentage | 56.00% | 57.00% | 53.00%
Daily Journal Non-Consolidated [Member] |  |  |
Management Incentive Plan Total Percentage of Pre Tax Earnings | 4.49% | 4.13% | 3.85%
Management Incentive Plan Total Amount Paid | $ 271,350 | $ 198,915 | $ 265,490
Journal Technologies [Member] |  |  |
Management Incentive Plan Total Percentage of Pre Tax Earnings | 8.30% | 7.07% |
Management Incentive Plan Total Amount Paid | $ 0 | $ 10,600 |
Daily Journal Consolidated [Member] |  |  |
Management Incentive Plan Total Percentage of Pre Tax Earnings | 8.20% | 8.20% | 8.20%
Management Incentive Plan Total Amount Paid | $ 0 | $ 0 | $ 0
Management Incentive Plan, Future Commitment [Member] |  |  |
Other Accrued Liabilities | 62,000 | 47,000 |
Increase (Decrease) in Other Accrued Liabilities | $ 15,000 | $ (733,000) |
Other Accrued Liabilities Impact on Earnings Per Share | $ 0.01 | $ 0.53 |
Finite-Lived Intangible Assets, Amortization Expense, Year Three | $ 0 |  |
Weighted Average Number of Shares Outstanding, Basic and Diluted | 1,380,746 | 1,380,746 | 1,380,746
Available-for-sale Securities | $ 166,634,000 | $ 166,041,000 |
Available-for-sale Securities, Gross Unrealized Gain (Loss) | 108,256,000 | 111,498,000 |
Deferred Tax Liabilities, Investments | 42,250,000 | 43,278,000 | $ 48,896,000
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Available-for-sale Securities |  | 376,000 |
Other Than Temporary Impairment Losses Investments, Portion Recognized in Earnings, Net of Taxes, Available-for-sale Securities |  | 230,000 |
Unrealized Loss on Securities |  |  | 0
Finite-Lived Intangible Assets, Net | 7,953,000 | 12,990,000 |
Finite-Lived Intangible Assets, Accumulated Amortization | $ 16,676,000 | 11,639,000 |
Finite-Lived Intangible Asset, Useful Life | 5 years |  |
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months | $ 4,895,000 |  |
Finite-Lived Intangible Assets, Amortization Expense, Year Two | 3,058,000 |  |
Amortization of Intangible Assets | 5,037,000 | 4,907,000 | 4,866,000
Goodwill | 13,400,000 | 13,400,000 |
Depreciation | $ 672,000 | 624,000 | 650,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period | 10 years |  |
Fair Value Inputs, Discount Rate | 6.00% |  |
Liability for Uncertainty in Income Taxes, Noncurrent | $ 2,723,000 | $ 2,991,000 | $ 3,244,000

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