Long-term Debt (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Long-term Debt
Total debt and capital lease obligations	$ 314,942	$ 331,025
Less amounts due within one year and short-term borrowings	(28,851)	(30,389)
Total long-term debt and capital lease obligations	286,091	300,636
DCEMB notes
Long-term Debt
Total debt and capital lease obligations	585	585
DCEMB Revenue Bonds (non recourse to the Company)
Long-term Debt
Total debt and capital lease obligations	38,700	38,700
Chesapeake Notes
Long-term Debt
Total debt and capital lease obligations	100,000	100,000
SLG Notes
Long-term Debt
Total debt and capital lease obligations	145,000	149,000
IMW assumed debt
Long-term Debt
Total debt and capital lease obligations	11,875	12,661
Capital lease obligations
Long-term Debt
Total debt and capital lease obligations	4,557	3,568
Purchase Note \| IMW
Long-term Debt
Total debt and capital lease obligations	11,657	23,983
Purchase Note \| Northstar
Long-term Debt
Total debt and capital lease obligations	1,879	1,848
Purchase Note \| Weaver
Long-term Debt
Total debt and capital lease obligations	$ 689	$ 680

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section H

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- Definition

Obligation related to long-term debt (excluding convertible debt) and capital leases, the portion which is due in one year or less in the future.

+ References

+ Details

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