Represents the common stock units to be issued as a percentage of cash compensation deferred.

No definition available.

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Represents the minimum cash compensation required in order to qualify for elective participation in the plan.

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Represents the number of equity-based payment instruments, excluding stock (or unit) options that are modified and settled in cash during the reporting period.

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No definition available.

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Represents the percentage of deferred compensation that is fully vested at all times and non-forfeitable.

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No definition available.

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The percentage of the deferred compensation representing the match that is contingent only on employment with the Company.

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No definition available.

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Represents the percentage of deferred compensation representing the match that vests on the sixth anniversary.

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No definition available.

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Represents the percentage of deferred compensation representing the match that vests on the third anniversary.

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No definition available.

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- Definition

The fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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No definition available.

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- Definition

Reductions in the entity's income taxes that arise when compensation cost (from other than stock options awards) recognized on the entity's tax return exceeds compensation cost from other than stock option awards recognized on the income statement. This element increases net cash provided by operating activities.

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No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Employee and Non-Employee Director Stock and Benefit Plans (Details 5) (USD $)	12 Months Ended					12 Months Ended										12 Months Ended						1 Months Ended
	Dec. 31, 2012 Restricted share awards	Dec. 31, 2011 Restricted share awards	Dec. 31, 2010 Restricted share awards	Dec. 31, 2012 Performance-based share awards	Dec. 31, 2012 Market-based share awards	Dec. 31, 2012 Performance-Based or Market-Based Restricted Stock Units	Dec. 31, 2011 Performance-Based or Market-Based Restricted Stock Units	Dec. 31, 2010 Performance-Based or Market-Based Restricted Stock Units	Dec. 31, 2012 Time-Based Restricted Stock Units	Dec. 31, 2011 Time-Based Restricted Stock Units	Dec. 31, 2010 Time-Based Restricted Stock Units	Dec. 31, 2012 Phantom share awards	Dec. 31, 2011 Phantom share awards	Dec. 31, 2010 Phantom share awards	Dec. 31, 2012 Market-based units	Dec. 31, 2012 2007 Plan Phantom share awards	Dec. 31, 2011 2007 Plan Phantom share awards	Dec. 31, 2010 2007 Plan Phantom share awards	Dec. 31, 2012 SUA Subplan	Dec. 31, 2011 SUA Subplan	Dec. 31, 2010 SUA Subplan	Jun. 30, 2003 SUA Subplan First amendment	Jan. 31, 2006 SUA Subplan Second amendment
Total Number of Shares
Outstanding at the beginning of the period (in shares)	3,055,304	2,935,323	1,224,457	180,476	497,355	792,058	982,881	56,067	2,263,246	1,952,442	1,168,390	397,747	259,370	91,013	68,803				71,580	364,167	677,379
Granted (in shares)	1,392,746	1,343,172	2,193,239			216,740	128,208	1,009,786	1,176,006	1,214,964	1,183,453	447,353	205,760	212,047
Vested (in shares)	(1,050,760)	(843,053)	(317,489)			(86,769)	(66,271)	(28,249)	(963,991)	(776,782)	(289,240)	(135,049)	(67,383)	(25,285)					(71,580)	(288,917)	(311,106)
Forfeited (in shares)	(335,955)	(380,138)	(164,884)			(244,198)	(252,760)	(54,723)	(91,757)	(127,378)	(110,161)	(14,341)		(18,405)						(3,670)	(2,106)
Outstanding at the end of the period (in shares)	3,061,335	3,055,304	2,935,323	180,476	497,355	677,831	792,058	982,881	2,383,504	2,263,246	1,952,442	695,710	397,747	259,370	68,803					71,580	364,167
Weighted Average Grant Date Fair Value
Outstanding at the beginning of the period (in dollars per share)	$ 17.49	$ 19.44	$ 27.03									$ 18.47	$ 18.51	$ 23.45					$ 33.95	$ 29.82	$ 29.32
Granted (in dollars per share)	$ 10.63	$ 16.65	$ 16.26									$ 11.33	$ 18.67	$ 16.96
Vested (in dollars per share)	$ 17.99	$ 23.29	$ 25.91									$ 19.46	$ 19.21	$ 23.45					$ 33.95	$ 28.98	$ 28.67
Forfeited (in dollars per share)	$ 26.10	$ 16.71	$ 21.02									$ 17.21		$ 18.25						$ 15.40	$ 32.54
Outstanding at the end of the period (in dollars per share)	$ 13.25	$ 17.49	$ 19.44									$ 13.72	$ 18.47	$ 18.51						$ 33.95	$ 29.82
Additional disclosures
Number of awards modified and settled in cash (in shares)	259,840
Unrecognized compensation costs	$ 18,200,000											$ 3,600,000
Weighted average period over which unrecognized compensation costs are expected to be recognized	1 year 8 months 19 days											1 year 10 months 17 days
Grant date fair value	12,200,000
Tax shortfalls related to the vesting	4,000,000	2,200,000	1,100,000
Vesting period																3 years
Share-based compensation expense	12,400,000	20,600,000	15,400,000													2,600,000	1,100,000	1,100,000		(200,000)	500,000
Tax benefit related to share-based compensation expense	5,000,000	8,400,000	6,200,000													700,000	300,000	400,000		(100,000)	200,000
Common stock units to be issued as a percentage of cash compensation deferred																						130.00%	120.00%
Percentage of deferred compensation that is fully vested at all times and non-forfeitable																						100.00%	100.00%
Percentage of the deferred compensation representing the match that is contingent only on employment with the Company																						30.00%	20.00%
Percentage of deferred compensation representing the match that vests on third anniversary																						50.00%	100.00%
Percentage of deferred compensation representing the match that vests on sixth anniversary																						50.00%
Minimum cash compensation required to qualify for elective participation under the plan																						$ 200,000	$ 200,000