Leases (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Leases [Line Items]
Operating leases expiration date		2028
Lease Expiration Year	2019
Depreciation expense for continuing operations		$ 77,500,000		$ 68,800,000		$ 63,500,000
Future minimum lease obligations, net of reversals		7,658,000	[1]	6,334,000	[1]	75,630,000	[1]
Minimum [Member]
Leases [Line Items]
Lease term range, years		5
Number of renewal options for extended terms		1
Maximum [Member]
Leases [Line Items]
Lease term range, years		10
Number of renewal options for extended terms		2
Continuing Operations [Member]
Leases [Line Items]
Rent expense, exclusive of related taxes		108,300,000		112,300,000		127,500,000
Discontinued Operations [Member]
Leases [Line Items]
Rent expense, exclusive of related taxes		11,600,000		12,200,000		91,800,000
Future minimum lease obligations, net of reversals		7,700,000		6,300,000		75,600,000
Discontinued Operations [Member] | Maximum [Member]
Leases [Line Items]
Lease Expiration Year		eight
Assets Under Capital Lease [Member]
Leases [Line Items]
Depreciation expense for continuing operations		$ 900,000		$ 600,000		$ 1,200,000

[1] Includes charges for newly vacated spaces and subsequent adjustments for accretion, revised estimates, and variances between estimated and actual charges, net of any reversals for terminated lease obligations.