Employee Benefit Plans (Stock Options Outstanding And Exercisable) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	240,834
Aggregate Intrinsic Value (in thousands)	$ 998
No. of Options Currently Exercisable (in shares)	142,565
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	419
Ranges Of Exercise Prices 26.62 - 33.90 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	102,483
Weighted-Average Exercise Price (in dollars per share)	$ 31.25
Weighted-Average Remaining Contractual Life (Months)	45 months
Aggregate Intrinsic Value (in thousands)	789
No. of Options Currently Exercisable (in shares)	52,565
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 32.28
Weighted-Average Remaining Contractual Life (Months)	21 months
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	350
Ranges Of Exercise Prices 26.62 - 33.90 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 26.62
Ranges Of Exercise Prices 26.62 - 33.90 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 33.90
Ranges Of Exercise Prices 35.09 - 40.88 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	138,351
Weighted-Average Exercise Price (in dollars per share)	$ 37.71
Weighted-Average Remaining Contractual Life (Months)	63 months
Aggregate Intrinsic Value (in thousands)	209
No. of Options Currently Exercisable (in shares)	90,000
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 38.61
Weighted-Average Remaining Contractual Life (Months)	40 months
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	$ 69
Ranges Of Exercise Prices 35.09 - 40.88 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 35.09
Ranges Of Exercise Prices 35.09 - 40.88 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 40.88

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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Weighted average remaining contractual term for fully vested and expected to vest options that are 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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