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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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

Reference 2: 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=27013229&loc=d3e301413-122809

Reference 3: 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

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)

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Stock-Based Compensation Plans (Performance Conditions Options Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Expense	$ 2,200,000	$ 1,400,000	$ 4,900,000	$ 9,437,000	$ 7,548,000	$ 4,100,000
Performance Condition Options
Description of award				During the year ended December 31, 2010, the Company's Board of Directors awarded a total of 1,130,700 performance condition options to certain of the Company's employees. Vesting of these options are subject to the Company achieving certain performance criteria established at the grant date and the individuals fulfilling a service condition (continued employment). As of December 31, 2013, the performance criteria of 825,340 of these options had been satisfied and these options will become exercisable based on the following vesting schedule: 25% on each of the first four anniversaries of the date of grant, which was February 20, 2010 (the date of grant). The Company recognized $277,000, $1.1 million and $153,000 of compensation expense during the years ended December 31, 2013, 2012 and 2011, respectively, related to these options. The next performance criteria is the acceptance of the BLA filing for Natpara by the FDA. The BLA was accepted by the FDA in January 2014 and will trigger approximately $111,000 of compensation expense related to these options being recognized in the first quarter of 2014. The Company utilized the Black-Scholes option pricing model to determine the grant date fair value of the awards. As of December 31, 2013, except for the 825,340 options discussed above, the Company does not believe that the achievement of the performance criteria for the other options is probable and therefore has not recognized any compensation expense related to those options during the years ended December 31, 2013, 2012 and 2011, respectively. Compensation expense will be recognized only once the performance condition is probable of being achieved and then only the cumulative amount related to the service condition that has been fulfilled. On May 19, 2010, the shareholders approved an ESPP whereby qualified employees are allowed to purchase limited amounts of the Company's common stock at the lesser of 85% of the market price at the beginning or end of the offering period. The shareholders have authorized 500,000 shares for purchase by employees. During the years ended December 31, 2013, 2012 and 2011, employees purchased 72,937, 45,553 and 37,065 shares, respectively, under the ESPP. The Company has 329,585 shares available for future purchase as of December 31, 2013.
Share-based Compensation Expense				$ 244,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				1,130,700
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized			3,500,000