Consolidated Statements of Changes in Stockholders' Equity (USD $) In Thousands	Total	Common Stock Member	Additional Paid In Capital Member	Retained Earnings Member	Accumulated Other Comprehensive Income Member	Noncontrolling Interest Member
Balance at Dec. 31, 2010	$ 901,478	$ 468	$ 242,390	$ (58,298)	$ (145)	$ 717,063
Balance (Share) at Dec. 31, 2010		46,894
Stock-based compensation	4,115		1,820			2,295
Common dividends	(8,192)			(8,192)
Net income (loss)	1,808			(2,609)		4,417
Conversion of restricted stock, net of shares withheld for taxes	(1,019)	3	(1,022)
Conversion of restricted stock, net of shares withheld for taxes (Shares)		283
Hedging gains or losses reclassified to earnings	980				184	796
Adjustment in fair value of derivatives	(1,384)				(258)	(1,126)
Non-controlling partner's impact of conversion of restricted units and options exercise	(1,348)					(1,348)
Distribution to non-controlling interest	(27,320)					(27,320)
Balance at Jun. 30, 2011	$ 869,118	$ 471	$ 243,188	$ (69,099)	$ (219)	$ 694,777
Balance (Share) at Jun. 30, 2011		47,177

Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Excludes common shares repurchased by the entity and held as Treasury shares. Shares outstanding equals shares issued minus shares held in treasury. Does not include common shares that have been repurchased.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

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Common stock cash dividend declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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Decrease in noncontrolling interest balance from payment of dividends or other distributions to noncontrolling interest holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(2)

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A1, A4, A5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 5
-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 29

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(1)

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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Total of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 25

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 26

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A3
-Appendix A

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Number of restricted stock for common stock

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The cash outflow to pay taxes for the conversion of restricted stock for common stock.

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Impact of conversion on Non Controlling Partners

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Net of tax effect of the reclassification adjustment for accumulated gains and losses including non controlling interest portion from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

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Change in accumulated gains and losses including non controlling interest portion from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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