Commitments and Contingencies, legal accruals and unasserted claims (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Loss Contingency Estimate
Accrual for legal proceedings and unasserted claims	$ 1.7	$ 1.7

Amount of loss contingency liability.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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