Retirement Plan (Details Textual) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Retirement Plan (Additional Textual) [Abstract]
Equity and debt investment fluctuations by plus or minus	20.00%
Contribution to ERISA plan	$ 750,000
Weighted-average discount rate and rate of increase in periodic pension costs	4.40%	4.40%
Expected long-term rate of return on plan assets	7.50%	7.50%
Equities [Member]
Retirement Plan (Textual) [Abstract]
Current investment policy target	65.00%
Investment mix target allocation	68.00%	66.00%
Debt [Member]
Retirement Plan (Textual) [Abstract]
Current investment policy target	25.00%
Investment mix target allocation	27.00%	29.00%
Money market funds [Member]
Retirement Plan (Textual) [Abstract]
Current investment policy target	10.00%
Investment mix target allocation	5.00%	5.00%

Defined benefit plan assets, target allocation period increase (decrease) percentage.

No definition available.

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- Definition

Defined benefit plan expected long term rate of return on plan assets.

+ References

No definition available.

+ Details

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- Definition

Defined benefit plan investment mix.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(2)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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