Share-Based And Other Deferred Compensation (LP Units, Acquisition-Related, 2006 Stock Incentive Plan, IPO Event-Based Awards, Deferred Cash Program) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 months	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Lp Units Convertible Conversion Ratio	1
LP Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested LP units	13,548
Unvested units	9,589
Lp Units Convertible Conversion Ratio	1
Amortization of LP Units	$ 22,189	$ 20,060	$ 8,552
Total compensation expense	40,297
Weighted-average period over which the compensation cost is expected to recognize, in months	24
Acquisition-Related [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Acquisition related awards vested
Acquisition related awards unvested	1,911
Amortization of acquisition related awards	6,621
Amortization of acquisition related deferred cash consideration	2,455
Forfeited event units
2006 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan shares remaining	7,434	9,549
IPO Event-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Of Event Based Awards	594	2
Unvested Event Based Awards		633
Expense Related To Vesting Of Event Based Awards		38
Event Based Awards Forfeited	(27)	(50)
Deferred Cash Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	6,982
Weighted-average period over which the compensation cost is expected to recognize, in months	38
Deferred cash consideration	9,153
Compensation expense related to deferred compensation program	1,938
Deferred compensation, vesting period, years	4
Unvested Acquisition-Related Equity Awards [Member] | Acquisition-Related [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	47,826
Weighted-average period over which the compensation cost is expected to recognize, in months	20
Compensation expense related to deferred compensation program	1,365
Deferred compensation, vesting period, in months	42
Unvested Acquisition-Related Equity Awards [Member] | Acquisition-Related [Member] | Lexicon [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense Related To Acquisition Related Deferred Compensation	413
Grant Of Acquisition Related Deferred Compensation	1,892
Deferred compensation, vesting period, in months	2
Class A [Member] | 2006 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Authorized Under Plan	20,000
Class A [Member] | IPO Event-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested units	546
Total compensation expense	$ 11,467
Class A [Member] | Restricted Stock [Member] | Acquisition-Related [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Acquisition Related Share Issuance	1,883
Class A [Member] | RSUs [Member] | IPO Event-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Original Grant Of Event Based Awards	2,286
RSUs convertible into Class A common Stock ratio	1