Shareholders' Equity (Issued Share Capital) (Details) $ in Millions	Mar. 31, 2016 USD ($) shares	Mar. 31, 2016 SFr / shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2015 SFr / shares
Stockholders' Equity Note [Abstract]
Common shares issued and fully paid, 2016 and 2015: CHF 4.10 per share \| shares	94,062,342		95,523,230
Common shares, par value \| SFr / shares		SFr 4.1		SFr 4.1
Total share capital \| $	$ 375.1		$ 386.7

Face amount or stated value per share of common stock.

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 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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