Employee Benefit Plans (Stock Options Outstanding And Exercisable) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	152,015
Aggregate Intrinsic Value (in thousands)	$ 1,296
No. of Options Currently Exercisable (in shares)	76,750
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	758
Ranges Of Exercise Prices Twenty Five Point Zero To Twenty Nine Point Ninety Nine [Member] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	2,250
Weighted-Average Exercise Price (in dollars per share)	$ 28.54
Weighted-Average Remaining Contractual Life (Years)	2 years 2 months
Aggregate Intrinsic Value (in thousands)	40
No. of Options Currently Exercisable (in shares)	2,250
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 28.54
Weighted-Average Remaining Contractual Life (Years)	2 years 2 months
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	40
Ranges Of Exercise Prices Twenty Five Point Zero To Twenty Nine Point Ninety Nine [Member] [Domain] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 25.00
Ranges Of Exercise Prices Twenty Five Point Zero To Twenty Nine Point Ninety Nine [Member] [Domain] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 29.99
Ranges Of Exercise Prices Thirty Point Zero To Thirty Four Point Ninety Nine [Member] [Domain] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	24,000
Weighted-Average Exercise Price (in dollars per share)	$ 31.76
Weighted-Average Remaining Contractual Life (Years)	4 years
Aggregate Intrinsic Value (in thousands)	355
No. of Options Currently Exercisable (in shares)	24,000
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 31.76
Weighted-Average Remaining Contractual Life (Years)	4 years
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	355
Ranges Of Exercise Prices Thirty Point Zero To Thirty Four Point Ninety Nine [Member] [Domain] [Domain] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 30
Ranges Of Exercise Prices Thirty Point Zero To Thirty Four Point Ninety Nine [Member] [Domain] [Domain] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 34.99
Ranges Of Exercise Prices Thirty Five Point Zero To Thirty Nine Point Ninety Nine [Member] [Domain] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	90,351
Weighted-Average Exercise Price (in dollars per share)	$ 37.44
Weighted-Average Remaining Contractual Life (Years)	4 years 7 months
Aggregate Intrinsic Value (in thousands)	822
No. of Options Currently Exercisable (in shares)	42,000
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 39.04
Weighted-Average Remaining Contractual Life (Years)	1 year 10 months
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	315
Ranges Of Exercise Prices Thirty Five Point Zero To Thirty Nine Point Ninety Nine [Member] [Domain] [Domain] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 35
Ranges Of Exercise Prices Thirty Five Point Zero To Thirty Nine Point Ninety Nine [Member] [Domain] [Domain] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 39.99
Ranges Of Exercise Prices Forty Point Zero To Forty Four Point Ninety Nine [Member] [Domain] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	22,453
Weighted-Average Exercise Price (in dollars per share)	$ 43.09
Weighted-Average Remaining Contractual Life (Years)	6 years 8 months
Aggregate Intrinsic Value (in thousands)	77
No. of Options Currently Exercisable (in shares)	8,500
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 40.88
Weighted-Average Remaining Contractual Life (Years)	3 years
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	48
Ranges Of Exercise Prices Forty Point Zero To Forty Four Point Ninety Nine [Member] [Domain] [Domain] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 40
Ranges Of Exercise Prices Forty Point Zero To Forty Four Point Ninety Nine [Member] [Domain] [Domain] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 44.99
Ranges Of Exercise Prices Forty Five Point Zero To Fifty Point Zero [Member] [Domain] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
No. of Options Outstanding (in shares)	12,961
Weighted-Average Exercise Price (in dollars per share)	$ 46.41
Weighted-Average Remaining Contractual Life (Years)	9 years 11 months
Aggregate Intrinsic Value (in thousands)	2
No. of Options Currently Exercisable (in shares)	0
Weighted-Average Exercise Price of Options Currently Exercisable (in dollars per share)	$ 0.00
Weighted-Average Remaining Contractual Life (Years)	0 years
Aggregate Intrinsic Value of Options Currently Exercisable (in thousands)	$ 0
Ranges Of Exercise Prices Forty Five Point Zero To Fifty Point Zero [Member] [Domain] [Domain] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 45
Ranges Of Exercise Prices Forty Five Point Zero To Fifty Point Zero [Member] [Domain] [Domain] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges Of Exercise Prices (in dollars per share)	$ 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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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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.

+ References

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-Publisher FASB

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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.

+ References

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-Publisher FASB

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

+ References

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-Publisher FASB

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

+ References

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-Publisher FASB

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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