Company Unit Options (Details 1) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Unit Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, beginning of period	451,574
Exercised	(40,246)
Foreited	(10,433)
Expired	0
Outstanding, end of period	400,895
Options exercisable at end of period	334,326
Unit Options Weighted Average Share Price [Abstract]
Outstanding, beginning of period	$ 6.99
Excercised	$ 5.06
Forfeited	$ 16.34
Expired	$ 0
Outstanding, End of period	$ 6.95
Weighted Average Contractual Term End Of Period [Abstract]
Options outstanding	6.7
Options excercisable	6.5
Aggregate Instrinsic Value End Of Period [Abstract]
Options outstanding	$ 4,201
Options exerciseable	$ 3,508
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable at end of period	37,500
Unit Options Weighted Average Share Price [Abstract]
Outstanding, End of period	$ 6.50

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date.

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-Name Accounting Standards Codification

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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 period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.

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The weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that lapsed during the reporting period.

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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.

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The weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncompliance with plan terms during the reporting period.

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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

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