Stockholders' Equity - Stock Options Granted (Details) (USD $)	95 Months Ended	3 Months Ended
Mar. 31, 2015	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted	9,055,000
Options Outstanding	4,580,130	4,580,130
Options Exercisable	1,885,130	1,885,130
April 22, 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		955,000
Option Exercise (Strike) Price		$ 56.00
Closing Stock Price on Date of Grant	50.53	$ 50.53
Options Outstanding	840,000	840,000
Options Exercisable	0	0
April 16, 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		205,000
Option Exercise (Strike) Price		$ 54.00
Closing Stock Price on Date of Grant	49.25	$ 49.25
Options Outstanding	140,000	140,000
Options Exercisable	0	0
April 17, 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		1,235,000
Option Exercise (Strike) Price		$ 54.00
Closing Stock Price on Date of Grant	49.01	$ 49.01
Options Outstanding	1,070,000	1,070,000
Options Exercisable	243,750	243,750
April 19, 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		410,000
Option Exercise (Strike) Price		$ 35.00
Closing Stock Price on Date of Grant	31.78	$ 31.78
Options Outstanding	320,000	320,000
Options Exercisable	60,000	60,000
April 20, 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		530,000
Option Exercise (Strike) Price		$ 30.00
Closing Stock Price on Date of Grant	27.13	$ 27.13
Options Outstanding	232,300	232,300
Options Exercisable	102,300	102,300
April 21, 2009 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		790,000
Option Exercise (Strike) Price		$ 27.00
Closing Stock Price on Date of Grant	17.61	$ 17.61
Options Outstanding	317,850	317,850
Options Exercisable	175,350	175,350
April 15, 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		550,000
Option Exercise (Strike) Price		$ 27.00
Closing Stock Price on Date of Grant	24.35	$ 24.35
Options Outstanding	170,250	170,250
Options Exercisable	115,250	115,250
April 17, 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted		4,380,000
Option Exercise (Strike) Price		$ 22.50
Closing Stock Price on Date of Grant	20.15	$ 20.15
Options Outstanding	1,489,730	1,489,730
Options Exercisable	1,188,480	1,188,480

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ 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)(iii)

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

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- Definition

Net number of share options (or share units) granted during the period.

+ 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)(iv)(1)

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

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

Reference 2: 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 per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

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