Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Condensed Consolidated Balance Sheets
Accumulated amortization of intangible assets	$ 24,232	$ 23,224	$ 22,623
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00	$ 1.00
Common stock, par value (in dollars per share)	$ 0.025	$ 0.025	$ 0.025
Common stock, shares authorized (in shares)	280,000,000	280,000,000	280,000,000
Common stock, shares issued (in shares)	84,950,618	84,633,845	84,516,567
Common stock, shares outstanding (in shares)	84,950,618	84,633,845	84,516,567

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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