Equity Compensation Plans - Options (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Equity Compensation Plans
Total compensation cost	$ 177,000
2014 Plan
Equity Compensation Plans
Number of shares authorized	375,000
Number of shares issuable	122,500
Stock options
Equity Compensation Plans
Granted (in shares)	0	0
Term of stock options granted	10 years
Exercised (in shares)	0	0
Total unrecognized compensation cost	$ 0
Shares
Beginning outstanding (in shares)	229,000
Ending outstanding (in shares)	229,000
Exercisable at end of period (in shares)	229,000
Weighted Average Exercise Price
Beginning outstanding (in dollars per share)	$ 28.28
Ending outstanding (in dollars per share)	$ 28.28
Exercisable at end of period (in dollars per share)	$ 28.28
Weighted Average Remaining Contractual Term (years)
Ending outstanding (in years)	1 year 10 months 24 days
Exercisable at end of period	1 year 10 months 24 days

The period of time, from the grant date until the time at which the share-based award expires.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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

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