Common Stock (Schedule of Stock Option Exercise Prices) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Amount Outstanding	652
Weighted Average Exercise Price	$ 19.99
Amount Exercisable	564
Weighted Average Exercise Price	$ 16.18
$0.01-5.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 0.01
Range of Exercise Prices, Maximum	$ 5.00
Amount Outstanding	140
Weighted Average Remaining Contractual Life	4 years 2 months
Weighted Average Exercise Price	$ 3.38
Amount Exercisable	140
Weighted Average Exercise Price	$ 3.38
5.01-10.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 5.01
Range of Exercise Prices, Maximum	$ 10.00
Amount Outstanding	193
Weighted Average Remaining Contractual Life	5 years 2 months
Weighted Average Exercise Price	$ 8.32
Amount Exercisable	193
Weighted Average Exercise Price	$ 8.32
10.01-15.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 10.01
Range of Exercise Prices, Maximum	$ 15.00
Amount Outstanding	22
Weighted Average Remaining Contractual Life	4 years 1 month
Weighted Average Exercise Price	$ 14.42
Amount Exercisable	22
Weighted Average Exercise Price	$ 14.42
15.01-20.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 15.01
Range of Exercise Prices, Maximum	$ 20.00
Amount Outstanding	30
Weighted Average Remaining Contractual Life	3 years 9 months
Weighted Average Exercise Price	$ 16.38
Amount Exercisable	30
Weighted Average Exercise Price	$ 16.38
25.01-30.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 25.01
Range of Exercise Prices, Maximum	$ 30.00
Amount Outstanding	73
Weighted Average Remaining Contractual Life	4 years 7 months
Weighted Average Exercise Price	$ 25.82
Amount Exercisable	52
Weighted Average Exercise Price	$ 25.89
30.01-35.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 30.01
Range of Exercise Prices, Maximum	$ 35.00
Amount Outstanding	69
Weighted Average Remaining Contractual Life	6 years 2 months
Weighted Average Exercise Price	$ 31.64
Amount Exercisable	69
Weighted Average Exercise Price	$ 31.64
40.01-45.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 40.01
Range of Exercise Prices, Maximum	$ 45.00
Amount Outstanding	51
Weighted Average Remaining Contractual Life	7 years 1 month
Weighted Average Exercise Price	$ 41.25
Amount Exercisable	34
Weighted Average Exercise Price	$ 41.25
50.01-55.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Minimum	$ 50.01
Range of Exercise Prices, Maximum	$ 55.00
Amount Outstanding	74
Weighted Average Remaining Contractual Life	8 years 2 months
Weighted Average Exercise Price	$ 53.78
Amount Exercisable	24
Weighted Average Exercise Price	$ 53.78

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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

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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 Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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 (c)(iii)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

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

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)

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

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (e)(1)

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

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- 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

Reference 1: 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

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