Share-Based Payments (Summary of Stock Option Transactions under Share-Based Payment Plans) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Outstanding at December 31, 2014, number of shares	734,539
Granted in 2015, numbers of shares	0
Exercised in 2015, number of shares	241,111
Forfeited or expired 2015, number of shares	0
Outstanding at December 31, 2015, number of shares	493,428	734,539
Exercisable at December 31, 2015, number of shares	493,428
Outstanding at December 31, 2014, weighted average exercise price	$ 19.52
Granted in 2015, weighted average exercise price	0.00
Exercised in 2015, weighted average exercise price	22.97
Forfeited or expired 2015, weighted average exercise price	0.00
Outstanding at December 31, 2015, weighted average exercise price	17.84	$ 19.52
Exercisable as December 31, 2015, weighted average exercise price	$ 17.84
Outstanding at December 31, 2015, weighted average remaining contractual life in years	2 years 10 months 25 days
Exercisable at December 31, 2015, weighted average remaining contractual life in years	2 years 10 months 25 days
Outstanding at December 31, 2015, aggregate intrinsic value	$ 7,767
Exerciseable at December 31, 2015, aggregate intrinsic value	7,767
Total intrinsic value of options exercised	2,200	$ 800	$ 1,300
Cash Incentive Plan [Member]
Share Based Compensation Liability Awards Amount Of Liability	$ 26,500	$ 21,900

The liability recorded in connection with our Cash Incentive Plan.

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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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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- 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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- Definition

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

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- Definition

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

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

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

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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