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Price of a single share of a number of saleable stocks of a company.

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Per share or per unit amount of equity securities issued.

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Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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Number of shares that have been repurchased and retired during the period.

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Shareholders' Equity (Details) - USD ($)		3 Months Ended	9 Months Ended
Shareholders' Equity (Details) - USD ($)	Jul. 31, 2018	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Stock Repurchased [Abstract]
Shares issued to non-qualified defined contribution retirement plans (in shares)			13,520	4,975
Shares issued to individuals (in shares)		2,400
Total consideration for shares to be purchased			$ 31,152,000
Minimum [Member]
Stock Repurchased [Abstract]
Share price of shares issued (in dollars per share)		$ 635	$ 635	$ 590
Maximum [Member]
Stock Repurchased [Abstract]
Share price of shares issued (in dollars per share)		$ 690	$ 690	$ 595
Estate of Former Director [Member]
Stock Repurchased [Abstract]
Number of shares of stock repurchased (in shares)	44,503
Purchase price (in dollars per share)	$ 700
Total consideration for shares to be purchased	$ 31,152,100