Significant Accounting Policies (Share-based Compensation) (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Abstract]
Advertising expense	$ 16,500,000	$ 13,500,000	$ 8,100,000
Product development costs	7,500,000	7,400,000	7,600,000
Common 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	80,701	80,701
Stock Compensation Plan [Member] \| Common 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)	72,566	18,805
Class A common stock available for issuance under the plan (shares)	249,882
Compensation expense related to share awards	4,400,000	1,700,000	6,500,000
Compensation expense related to share awards, net of tax	2,800,000	1,100,000	4,200,000
Stock Compensation Plan [Member] \| Common 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)	83,814
Compensation expense related to share awards	800,000	500,000	300,000
Compensation expense related to share awards, net of tax	500,000	300,000	200,000
Restricted stock \| Common 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)	8,944	4,938	3,039
Amount of directors, annual retainer paid in restricted shares	69,000	49,500	29,250
Annual non-employee directors retainer amount	$ 125,000	$ 90,000	$ 53,626
Percentage of annual retainer that may be received in shares of Class A stock (percent)	100.00%
Voluntary shares \| Common 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)	1,991	1,356	944
Date of Award \| Stock Compensation Plan [Member] \| Common Class A \| 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
Date of Award \| Stock Compensation Plan [Member] \| Common Class A \| 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
Participants Death or Permanent Disability \| Stock Compensation Plan [Member] \| Common Class A \| 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
Participants Retirement from Board of Directors \| Stock Compensation Plan [Member] \| Common Class A \| 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
Minimum Age Of Director Upon Retirement From Board \| Stock Compensation Plan [Member] \| Common Class A \| 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

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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

-Name Accounting Standards Codification

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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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