Segment Information - Segment Assets (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	$ 1,888.1	$ 1,941.9
Reportable Segment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	1,677.7	1,806.9
RESV [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	647.0	672.0
TECH [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	313.3	323.4
DMS [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	393.4	424.8
RHC [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	134.5	168.4
CES [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets	189.5	218.3
Unallocated Amount to Segment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Cash and cash equivalents, including current restricted cash	144.9	58.3
Prepaid income taxes	29.3	38.7
Other assets, including long-term restricted investments and marketable securities	$ 36.2	$ 38.0