The amount of company stock received, in lieu of cash payment, for the exercise of stock options.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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Amount of increase (decrease) in current liabilities classified as other.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The number of shares issued as [noncash or part noncash] consideration for a business or asset acquired. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The fair value of stock issued in noncash financing activities.

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Number of new stock issued during the period.

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Note 4 - Supplemental Cash Flow Information (Details Textual) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 01, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018	Dec. 31, 2017
Income Taxes Paid				$ 700	$ 3,700
Interest Paid, Excluding Capitalized Interest, Operating Activities				$ 800	$ 300
Company Stock Received in Lieu of Cash Stock Options Exercised		1,031	27,341	6,894	43,841
Stock Issued During Period, Shares, New Issues		6,000	71,599	26,234	113,143
Contract with Customer, Asset, Net, Current, Total	$ 43,300	$ 46,826		$ 46,826		$ 46,800
Increase (Decrease) in Inventories, Total				$ (2,953)	$ (1,632)
CID Resources [Member]
Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Shares Issued				150,094
Stock Issued				$ 3,800
Accounting Standards Update 2014-09 [Member]
Increase (Decrease) in Inventories, Total	(24,900)
Increase (Decrease) in Accounts Payable, Total	2,600
Increase (Decrease) in Other Current Liabilities	1,100
Increase (Decrease) in Deferred Income Taxes	$ (3,500)