Shareholders' Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended
Feb. 20, 2015	Mar. 31, 2015
Dividends
Cash dividends declared per common share	$ 0.25
Dividends paid		$ 28.8us-gaap_DividendsCommonStockCash
Governance agreement \| GSK \| Common stock
Shareholders' Equity
Common stock purchased (in shares)		92,674
Aggregate purchase price of common stock		$ 1.7

Number of shares issued during the period as a result of private placement to a related party.

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Value stock issued during the period as a result of private placement to a related party, net of issuance cost.

+ References

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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