Discount interest rate to prime.

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- Definition

Financial instruments.

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The maximum length of time, in years, that the amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer, are in a continuous unrealized loss/gain position.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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 carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of the fee for available but unused credit capacity under the credit facility.

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Date the credit facility terminates, in YYYY-MM-DD format.

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The effective interest rate during the reporting period.

+ References

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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- Definition

The cash outflow to reacquire common stock during the period.

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Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Sep. 08, 2021
Financial Instruments [Line Items]
Period cash equivalents and short-term investments have been in continuous unrealized gain (loss) position, years, maximum	1 year
Non controlling interest	$ 1,200,000
Aggregate maximum payments of repurchases of common stock	815,000	$ 3,828,000
Cash and cash equivalents, unrestricted	89,845,000		$ 109,408,000
Maximum [Member]
Financial Instruments [Line Items]
Gain (loss) from investment in affiliate	$ (100,000)	$ (100,000)
Credit Agreement \| Wintrust Bank [Member]
Financial Instruments [Line Items]
Discount interest rate to prime	1.00%
Credit Agreement \| Wintrust Bank [Member] \| Minimum [Member] \| Prime [Member]
Financial Instruments [Line Items]
Line of credit facility, interest rate	3.00%
Credit Agreement \| Revolving Credit Facility \| Wintrust Bank [Member]
Financial Instruments [Line Items]
Credit facility borrowings	$ 0		0
Credit Agreement \| Revolving Credit Facility [Member] \| Wintrust Bank [Member]
Financial Instruments [Line Items]
Revolving credit facility maturity date	Sep. 08, 2024
Revolving credit facility				$ 125,000,000.0
Credit Agreement \| Revolving Credit Facility [Member] \| Wintrust Bank [Member] \| Maximum [Member]
Financial Instruments [Line Items]
Aggregate commitment amount	$ 50,000,000.0
Aggregate maximum payments of repurchases of common stock	$ 100,000,000.0
Percentage of aggregate amount of loan commitments	125.00%
Equity Affiliate [Member]
Financial Instruments [Line Items]
Percentage of investment in equity affiliate	30.70%
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Instruments [Line Items]
Total short-term investments (available for sale), Fair value	$ 33,100,000		$ 40,100,000
Federal Agencies Debt Securities within Cash and Cash Equivalents [Member] \| Level 2 [Member]
Financial Instruments [Line Items]
Total short-term investments (available for sale), Fair value	$ 3,000,000.0