Stockholders' Equity and Equity Compensation Plans (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2014
Stockholders Equity And Equity Compensation Plans [Line Items]
Remaining number of shares available for repurchase	3,300,000
Repurchase of common stock for employee tax withholdings, shares	123,000	110,000
Repurchase of common stock for tax withholdings, value	$ 7,800	$ 5,200
Cash dividends declared per common share	$ 0.265	$ 0.25
Cash dividend	$ 8,600	$ 8,200
Stock warrants term			10 years
Stock warrants, exercise price			$ 26.68
Performance based awards granted to executive management and certain key employees shares	120,000,000,000
Vesting maturity date	first quarter of 2024
Vesting period	2 years
Stock-based compensation expense	$ 5,581	$ 5,395
Market-based Awards
Stockholders Equity And Equity Compensation Plans [Line Items]
Awards vested	40,000
Restricted common stock
Stockholders Equity And Equity Compensation Plans [Line Items]
Vesting period	3 years
Awards vested	339,000
Comcast
Stockholders Equity And Equity Compensation Plans [Line Items]
Issuance of stock warrants			2,900,000
Stock warrants issued	1,000,000.0
Stock warrants vested	0
SEC Rule 10b5-1 Plan
Stockholders Equity And Equity Compensation Plans [Line Items]
Repurchase of common stock, shares	266,000	142,000
Total amount paid	$ 16,000	$ 6,500
Weighted-average price per share	$ 60.13	$ 45.94

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The remaining number of stock warrants vested at the filing date.

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Share based compensation arrangement by share based payment award award vesting maturity.

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Stockholders equity and equity compensation plans.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Net number of share options (or share units) granted during the period.

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