Commitments and Contingencies Commitments and Contingencies, Guarantees and Indemnifications (Details) (Indemnification Agreement, Obligations Under Sale Of Sharyland, USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Indemnification Agreement | Obligations Under Sale Of Sharyland
Guarantor Obligations [Line Items]
Guarantee issued and outstanding	$ 37.1	$ 37.1
Guarantor Obligations, Current Carrying Value	$ 0.4	$ 0.4