Condensed Consolidated Statement Of Shareholders' Equity (USD $) In Thousands	Common Shares	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Shares	Total
Balances - value at Dec. 31, 2010	$ 6,109	$ 707,138	$ 413,212	$ (6,962)	$ (272)	$ 1,119,225
Balances - shares at Dec. 31, 2010	61,085					61,085
Stock-based compensation expense		2,640				2,640
Shares repurchased and retired - shares	(1,453)
Shares repurchased and retired - value	(146)	(15,610)	(8,924)			(24,680)
Stock options exercised - shares	130
Stock options exercised - value	13	1,442				1,455
Issuance of restricted shares, net of forfeitures - shares	181
Issuance of restricted shares, net of forfeitures - value	18	(18)
Excess tax benefit of stock-based compensation		223				223
Comprehensive income			29,214	6,624		35,838
Balances - value at Jun. 30, 2011	$ 5,994	$ 695,815	$ 433,502	$ (338)	$ (272)	$ 1,134,701
Balances - shares at Jun. 30, 2011	59,943					59,943

This element represents the amount of recognized share-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 39

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64
-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A91

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Tax benefit associated with any share-based compensation plan other than an employee stock ownership plan (ESOP). The tax benefit results from the deduction by the entity on its tax return for an award of stock that exceeds the cumulative compensation cost for common stock or preferred stock recognized for financial reporting. Includes any resulting tax benefit that exceeds the previously recognized deferred tax asset (excess tax benefits).

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

+ References

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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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References

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

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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 30

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-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
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-Name Accounting Research Bulletin (ARB)
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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

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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 26

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-Name Accounting Research Bulletin (ARB)
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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Number of shares issued during the period as a result of the exercise of stock options.

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Value of stock related to Restricted Stock Awards issued during the period, net of the stock value of such awards forfeited.

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Number of shares that have been repurchased and retired during the period.

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Value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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