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Number of shares of equity interests issued or issuable to acquire entity.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Number of new stock issued during the period.

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Long-term Investments - Additional Information (Details) $ / shares in Units, shares in Millions			1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 19, 2019 shares	Jun. 30, 2019 shares	Apr. 24, 2018 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2018 item
Long-term Investments
Impairment of equity method investments				$ 0	$ 0	$ 0	$ 0
Purchase of shares \| shares	2.0
Number of common stock issued \| shares		0.6
Carrying amount of equity investment sold					3,200,000		3,200,000
Gain (loss) on the sale of equity investment				$ 7,000	$ (40,000)	$ (8,000)	$ (606,000)
Seasail Ventures Limited [Member]
Long-term Investments
Percentage of equity ownership			40.00%
BDCG
Long-term Investments
Percentage of equity ownership			20.00%	60.00%		60.00%
Number of unrelated party \| item								2
Cash paid to acquire entity			$ 2,000,000.0
Value of capital stock issued			$ 7,800,000
Number of common stock issued \| shares			3.0
Share price of capital stock issued \| $ / shares			$ 2.60
Total purchase price paid			$ 9,800,000			$ 9,800,000