Fair Value Measurements (Financial Instruments Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified
|
Dec. 31, 2012
|
Dec. 31, 2011
|
Dec. 31, 2010
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
|
$ 47.6 |
|
Investment Owned, at Fair Value |
|
552.8 |
|
Contingent consideration at Fair Value |
|
10.3 |
|
Total liabilities at fair value |
|
10.3 |
|
Municipal Bonds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
4.5 |
|
US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
5.1 |
|
Total Assets at Fair Value |
|
600.4 |
|
Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
|
31.8 |
|
Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0.9 |
|
US Government Agencies Debt Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
5.3 |
|
Fair Value, Inputs, level 1 [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
|
36.9 |
|
Investment Owned, at Fair Value |
|
552.8 |
|
Contingent consideration at Fair Value |
|
0 |
|
Total liabilities at fair value |
|
0 |
|
Fair Value, Inputs, level 1 [Member] | Municipal Bonds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 1 [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
5.1 |
|
Total Assets at Fair Value |
|
589.7 |
|
Fair Value, Inputs, level 1 [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
|
31.8 |
|
Fair Value, Inputs, level 1 [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 1 [Member] | US Government Agencies Debt Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 2 [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
|
10.7 |
|
Investment Owned, at Fair Value |
|
0 |
|
Contingent consideration at Fair Value |
|
0 |
|
Total liabilities at fair value |
|
0 |
|
Fair Value, Inputs, level 2 [Member] | Municipal Bonds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
4.5 |
|
Fair Value, Inputs, level 2 [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Total Assets at Fair Value |
|
10.7 |
|
Fair Value, Inputs, level 2 [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 2 [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0.9 |
|
Fair Value, Inputs, level 2 [Member] | US Government Agencies Debt Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
5.3 |
|
Fair Value, Inputs, level 3 [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
|
0 |
|
Investment Owned, at Fair Value |
|
0 |
|
Contingent consideration at Fair Value |
|
10.3 |
|
Total liabilities at fair value |
|
10.3 |
|
Fair Value, Inputs, level 3 [Member] | Municipal Bonds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 3 [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Total Assets at Fair Value |
|
0 |
|
Fair Value, Inputs, level 3 [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 3 [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Fair Value, Inputs, level 3 [Member] | US Government Agencies Debt Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
|
0 |
|
Fair Value, Measurements, Recurring [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
56.6 |
|
|
Investment Owned, at Fair Value |
721.7 |
|
|
Total Assets at Fair Value |
778.3 |
|
|
Derivative Liability, Fair Value, Gross Liability |
1.0 |
|
|
Contingent consideration at Fair Value |
12.6 |
|
|
Total liabilities at fair value |
13.6 |
|
|
Fair Value, Measurements, Recurring [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
17.5 |
|
|
Fair Value, Measurements, Recurring [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
38.7 |
|
|
Fair Value, Measurements, Recurring [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
0.4 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
56.2 |
|
|
Investment Owned, at Fair Value |
721.7 |
|
|
Total Assets at Fair Value |
777.9 |
|
|
Derivative Liability, Fair Value, Gross Liability |
0 |
|
|
Contingent consideration at Fair Value |
0 |
|
|
Total liabilities at fair value |
0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
17.5 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
38.7 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 1 [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
0.4 |
|
|
Investment Owned, at Fair Value |
0 |
|
|
Total Assets at Fair Value |
0.4 |
|
|
Derivative Liability, Fair Value, Gross Liability |
1.0 |
|
|
Contingent consideration at Fair Value |
0 |
|
|
Total liabilities at fair value |
1.0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 2 [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
0.4 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Marketable Securities at Fair Value |
0 |
|
|
Investment Owned, at Fair Value |
0 |
|
|
Total Assets at Fair Value |
0 |
|
|
Derivative Liability, Fair Value, Gross Liability |
0 |
|
|
Contingent consideration at Fair Value |
12.6 |
10.3 |
9.5 |
Total liabilities at fair value |
12.6 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | US Treasury Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | Mutual funds [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Trading Securities at Fair Value |
0 |
|
|
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, level 3 [Member] | Asset-backed Securities [Member]
|
|
|
|
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
Available-for-sale Securities at Fair Value |
$ 0 |
|
|