Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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

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-URI http://asc.fasb.org/extlink&oid=6528421

+ Details

Summary of Significant Accounting (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of significant accounting policies (Textual) [Abstract]
Deferred income tax liability	$ 0
Weighted average of common shares outstanding	10,338,000	10,319,000	10,254,000
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average outstanding stock options	671,977	544,342	344,135
Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Investments in joint ventures	50.00%
Defined Benefit Plan Actuarial Gain Loss Percentage	10.00%
Maximum [Member] \| Land improvements [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Property, plant and equipment, estimated useful life	P20Y
Maximum [Member] \| Building [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Property, plant and equipment, estimated useful life	P50Y
Maximum [Member] \| Machinery and equipment [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Property, plant and equipment, estimated useful life	P25Y
Minimum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Investments in joint ventures	20.00%
Defined Benefit Plan Actuarial Gain Loss Percentage	10.00%
Minimum [Member] \| Land improvements [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Property, plant and equipment, estimated useful life	P15Y
Minimum [Member] \| Building [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Property, plant and equipment, estimated useful life	P25Y
Minimum [Member] \| Machinery and equipment [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Property, plant and equipment, estimated useful life	P3Y