No authoritative reference available.

No definition available.

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- Definition

No authoritative reference available.

+ References

No definition available.

+ Details

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- Details

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- Definition

As of the balance sheet date, the total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options that are exercisable.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(2)

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

+ Details

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- Definition

The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

+ References

+ Details

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- Definition

As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

+ References

+ Details

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- Definition

The weighted-average period between the balance sheet date and expiration date for fully vested and expected to vest options that are exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

+ References

+ Details

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- Definition

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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

+ Details

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted-average period between the balance sheet date and expiration date for fully vested and expected to vest options outstanding, which may be expressed in a decimal value for number of years.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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

+ Details

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- Details

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

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

+ Details

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Period Type:	duration

- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

+ Details

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Share Based Compensation (Details 3) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Stock Options Outstanding Summary [Line Items]
Exercise Price, Lower Range Limit	$ 16.97	$ 3.91	$ 1.49	$ 0.25
Exercise Price, Upper Range Limit	$ 98.87	$ 98.87	$ 98.87	$ 98.87
16.97 - 19.18 [Member]
Stock Options Outstanding Summary [Line Items]
Exercise Price, Lower Range Limit	$ 16.97
Exercise Price, Upper Range Limit	$ 19.18
Minimum Range of Exercise Price	$ 16.97
Exercise Price, Upper Range Limit	$ 19.18
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Number Outstanding	70
Weighted Average Remaining Contractual Life	2.37
Weighted Average Exercise Price	$ 17.44
Aggregate Intrinsic Value	$ 853
Number Outstanding	70
Weighted Average Remaining Contractual Life	2.37
Weighted Average Exercise Price	$ 17.44
Aggregate Intrinsic Value	853
25.08 - 55.58 [Member]
Stock Options Outstanding Summary [Line Items]
Exercise Price, Lower Range Limit	$ 25.08
Exercise Price, Upper Range Limit	$ 55.58
Minimum Range of Exercise Price	$ 25.08
Exercise Price, Upper Range Limit	$ 55.58
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Number Outstanding	637
Weighted Average Remaining Contractual Life	3.60
Weighted Average Exercise Price	$ 38.69
Aggregate Intrinsic Value	179
Number Outstanding	637
Weighted Average Remaining Contractual Life	3.60
Weighted Average Exercise Price	$ 38.69
Aggregate Intrinsic Value	179
46.05 - 65.04 [Member]
Stock Options Outstanding Summary [Line Items]
Exercise Price, Lower Range Limit	$ 46.05
Exercise Price, Upper Range Limit	$ 65.04
Minimum Range of Exercise Price	$ 46.05
Exercise Price, Upper Range Limit	$ 65.04
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Number Outstanding	179
Weighted Average Remaining Contractual Life	4.53
Weighted Average Exercise Price	$ 56.67
Aggregate Intrinsic Value	0
Number Outstanding	179
Weighted Average Remaining Contractual Life	4.53
Weighted Average Exercise Price	$ 56.67
Aggregate Intrinsic Value	0
49.05 - 65.94 [Member]
Stock Options Outstanding Summary [Line Items]
Exercise Price, Lower Range Limit	$ 49.05
Exercise Price, Upper Range Limit	$ 65.94
Minimum Range of Exercise Price	$ 49.05
Exercise Price, Upper Range Limit	$ 65.94
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Number Outstanding	373
Weighted Average Remaining Contractual Life	5.31
Weighted Average Exercise Price	$ 54.58
Aggregate Intrinsic Value	0
Number Outstanding	373
Weighted Average Remaining Contractual Life	5.31
Weighted Average Exercise Price	$ 54.58
Aggregate Intrinsic Value	0
51.14 - 98.87 [Member]
Stock Options Outstanding Summary [Line Items]
Exercise Price, Lower Range Limit	$ 51.14
Exercise Price, Upper Range Limit	$ 98.87
Minimum Range of Exercise Price	$ 51.14
Exercise Price, Upper Range Limit	$ 98.87
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Number Outstanding	200
Weighted Average Remaining Contractual Life	6.40
Weighted Average Exercise Price	$ 70.51
Aggregate Intrinsic Value	0
Number Outstanding	200
Weighted Average Remaining Contractual Life	6.40
Weighted Average Exercise Price	$ 70.51
Aggregate Intrinsic Value	$ 0