Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Consolidated Balance Sheets [Abstract]
Properties and equipment, accumulated depreciation	$ 264,075	$ 248,370
Identifiable intangible assets, accumulated amortization	$ 34,651	$ 33,283
Capital stock - authorized	80,000,000	80,000,000
Capital stock - par value	$ 1	$ 1
Capital stock - issued	35,737,995	35,311,418
Treasury stock	19,808,981	19,438,358

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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