Significant Accounting Policies (Share-based Compensation) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting Policies [Abstract]
Advertising expense	$ 20,400,000us-gaap_AdvertisingExpense	$ 20,100,000us-gaap_AdvertisingExpense	$ 16,500,000us-gaap_AdvertisingExpense
Product development costs	9,600,000us-gaap_ResearchAndDevelopmentExpense	8,100,000us-gaap_ResearchAndDevelopmentExpense	7,500,000us-gaap_ResearchAndDevelopmentExpense
Shares Outstanding Class A
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class A common stock available for issuance under the plan (shares)	80,701
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Executives
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the year under the Company's stock compensation plans (shares)	32,591	16,123
Class A common stock available for issuance under the plan (shares)	201,168
Compensation expense related to share awards	1,800,000	900,000	4,400,000
Compensation expense related to share awards, net of tax	1,200,000	600,000	2,800,000
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Non-employee directors
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class A common stock available for issuance under the plan (shares)	61,261
Compensation expense related to share awards	600,000	600,000	800,000
Compensation expense related to share awards, net of tax	400,000	400,000	500,000
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Participant's Retirement Date \| Executives
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of restrictions on stock assignment, pledges or transfers	5 years
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Date of award \| Executives
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of restrictions on stock assignment, pledges or transfers	10 years
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Date of award \| Non-employee directors
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of restrictions on stock assignment, pledges or transfers	10 years
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Participants retirement from board of directors \| Non-employee directors
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of restrictions on stock assignment, pledges or transfers	5 years
Stock Compensation Plan [Member] \| Shares Outstanding Class A \| Minimum age of director upon retirement from board \| Non-employee directors
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of restrictions on stock assignment, pledges or transfers	70 years
Restricted stock \| Shares Outstanding Class A \| Non-employee directors
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the year under the Company's stock compensation plans (shares)	10,446	9,472	8,944
Amount of directors, annual retainer paid in restricted shares	69,000	69,000	69,000
Annual non-employee directors retainer amount	$ 125,000	$ 125,000	$ 125,000
Percentage of annual retainer that may be received in shares of Class A stock (percent)	100.00%
Voluntary shares \| Shares Outstanding Class A \| Non-employee directors
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the year under the Company's stock compensation plans (shares)	1,335	1,300	1,991

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Share-based Compensation BY Share-based Payment Awrd, Annual Retainer Convertible To Class A Common Stock, Percentage

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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-Publisher FASB

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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