Fair Value Measurements Fair Value, Reconciliation of Level 3 - Liabilities (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		$ 125,018	$ 122,525	$ 125,018	$ 122,525	$ 129,625	$ 130,725	$ 0	$ 0
Contingent Consideration, Beginning Value		13,938	1,373	10,781	1,983
Contingent Consideration, Reclass		0	0	(285)	(331)
(Gain) loss, net from changes in fair value of contingent consideration	[1]	850	(424)	4,292	(703)
Contingent Consideration, Ending Value		14,788	233	14,788	233
Fair Value, Measurement with Unobservable Inputs, Unrealized Gain Loss	[2]	850	(857)	4,166	(1,091)
Convertible debt securities [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		$ 10,573	$ 8,026	$ 10,573	$ 8,026	$ 10,173	$ 10,116	$ 2,757	$ 2,527

[1] Changes in the fair value of contingent consideration liabilities are classified within "Acquisition-related expense (benefit), net" on the condensed consolidated statements of operations.

[2] Represents the unrealized losses or gains recorded in earnings and/or other comprehensive income (loss) during the period for assets and liabilities classified as Level 3 that are still held (or outstanding) at the end of the period.