Notes Payable (Details) (USD $)	0 Months Ended	6 Months Ended
Jan. 04, 2013	Jun. 30, 2013
Notes Payable
Upfront cash proceeds		$ 175,000,000
Notes Payable
Notes Payable
Aggregate principal amount of notes issued in private placement	175,000,000
Annual interest rate of notes (as a percent)	11.00%
Percentage of net sales of LINZESS considered to determine quarterly payments on the notes		7.50%
Estimated principal payments		0
Margin over U.S. Treasury Rate		1.00%
Upfront cash proceeds	175,000,000
Discount on issuance of debt	400,000
Debt issuance costs capitalized	7,300,000
Estimated fair value		$ 183,800,000
Notes Payable \| From and including January 1, 2014 to and including December 31, 2014
Notes Payable
Redemption Percentage		112.00%
Notes Payable \| From and including January 1, 2015 to and including December 31, 2015
Notes Payable
Redemption Percentage		105.50%
Notes Payable \| From and including January 1, 2016 to and including December 31, 2016
Notes Payable
Redemption Percentage		102.75%
Notes Payable \| From and including January 1, 2017 and thereafter
Notes Payable
Redemption Percentage		100.00%

Represents the percentage price of the principal amount being redeemed at which debt can be redeemed by the issuer.

No definition available.

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- Definition

Represents the percentage of net sales of a specified product considered to determine the quarterly payments under the debt arrangement.

+ References

No definition available.

+ Details

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- Definition

Margin above the U.S. Treasury rate with a comparable maturity used to discount the principal and interest payments on the notes to determine the redemption price if redeemed prior to January 1, 2014.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

-Paragraph 19

-Article 5

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-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.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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-Publisher FASB

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The cash inflow from a borrowing supported by a written promise to pay an obligation.

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-Name Accounting Standards Codification

-Glossary Financing Activities

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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