Stock-Based Compensation Plans (Information Regarding Stock Options) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted during period	0
Shares
Outstanding — beginning of year	97,962	115,362	145,338
Exercised	0	(17,400)	(24,576)
Canceled	0	0	(5,400)
Outstanding — end of year	97,962	97,962	115,362
Exercisable — end of year	97,962	97,962	115,362
Weighted Average Exercise Price
Outstanding — beginning of year	$ 16.61	$ 15.00	$ 13.90
Exercised	$ 0.00	$ 5.91	$ 10.15
Canceled	$ 0.00	$ 0.00	$ 7.65
Outstanding — end of year	$ 16.61	$ 16.61	$ 15.00
Exercisable — end of year	$ 16.61	$ 16.61	$ 15.00
Weighted Average Remaining Contractual Life	1 year 9 months 18 days	2 years 9 months 18 days
Total intrinsic value of stock options exercised	$ 0	$ 800,000	$ 700,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost Related To Outstanding Stock Option awards	0
General expiration period, from date of grant or time of termination	10 years
Options granted during period	0	0	0
Weighted Average Exercise Price
Number of stock options vested	$ 0	$ 0	$ 0
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General vesting period	1 year
Stock Options \| Minimum \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General vesting period	1 year
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General vesting period	5 years
Stock Options \| Maximum \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General vesting period	3 years

Unrecognized Compensation Cost Related To Outstanding Stock Option awards

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

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

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Number of share options (or share units) exercised during the current period.

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