Investments (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Investments
Investment in joint ventures at beginning of the period	$ 21,831	$ 15,239
Investment	11,219	5,636	8,943
Earnings from joint ventures	3,526	1,759	1,295
Distribution		(802)
Transfer to consolidated subsidiary	(13,090)
Investment in joint ventures at end of the period	23,485	21,831	15,239
WOLF
Investments
Investment in joint ventures at beginning of the period	10,065	9,863
Earnings from joint ventures	3,025	1,004
Distribution		(802)
Transfer to consolidated subsidiary	(13,090)
Investment in joint ventures at end of the period		10,065
WMES
Investments
Investment in joint ventures at beginning of the period	11,766	5,376
Investment	11,219	5,635
Earnings from joint ventures	500	755
Investment in joint ventures at end of the period	$ 23,485	$ 11,766

This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Publisher FASB

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher SEC

-Name Regulation S-X (SX)

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-Name Accounting Standards Codification

-Topic 323

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-Publisher FASB

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-Topic 225

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Represents the balance of equity method investments that has been disposed off as a result of acquisition during the reporting period.

+ References

No definition available.

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