Note 11. Investments - Investments - Equity securities without readily determinable fair value Textuals (Details) $ in Millions	Mar. 31, 2019 USD ($)
Investment in privately held company	$ 2.0
Other Assets \| Preferred Stock
Equity securities without readily determinable fair value	$ 0.5

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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