Earnings Per Common Share And Share Awards Summary Of Share-Based Award Transactions (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number Of Shares, Options exercised	(1,500)	(1,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, Options exercised	$ 36.79	$ 27.21
StockOptionsAndStockAppreciationRightsSARS [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number Of Shares, Outstanding Beginning Balance	21,000	19,000
Number Of Shares, Options/SARs cancelled/forfeited/expired	0	0
Number Of Shares, Outstanding Ending Balance	17,500	21,000	19,000
Number Of Shares, Exercisable as of March 31, 2015	17,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, Outstanding Beginning Balance	$ 51.30	$ 45.74
Weighted Average Exercise Price, Options/SARs cancelled/forfeited/expired	$ 0.00	$ 0.00
Weighted Average Exercise Price, Outstanding Ending Balance	$ 52.94	$ 51.30	$ 45.74
Weighted Average Exercise Price, Exercisable as of March 31, 2015	$ 52.94
Average Remaining Contractual Term, Outstanding Beginning Balance	4 years 0 months 18 days	3 years 7 months 20 days	3 years 5 months 4 days
Average Remaining Contractual Term, Exercisable as of March 31, 2015	4 years 0 months 18 days
Aggregate Intrinsic Value, Outstanding Beginning Balance	$ 453,510	$ 669,610
Aggregate Intrinsic Value, Outstanding Ending Balance	369,255	453,510	669,610
Aggregate Intrinsic Value, Exercisable as of March 31, 2015	$ 369,255
SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number Of Shares, SARs granted	0	4,500
Number Of Shares, Options exercised	(2,000)	(1,500)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, SARs granted	$ 0.00	$ 68.70
Weighted Average Exercise Price, Options exercised	$ 47.88	$ 49.04

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

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