Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2023

Incentive Plans

Market Performance Based Awards

		Market
		Performance
	RMS Relative	Vesting
Level	Market Performance	Percentage
Below Threshold Level	≤ -500 basis points	0	%
Threshold Level	-500 basis points	25	%
Target Level	0 basis points	50	%
High Level	≥ 500 basis points	100	%

Schedule of Valuation Assumptions

	Expected Stock Price		Risk-Free Interest
Award Date	Volatility		rate
January 1, 2021	27	%	0.17	%
February 25, 2021	26	%	0.31	%
January 1, 2022	26	%	0.97	%
January 1, 2023	32	%	4.18	%

Schedule of compensation expense and unearned compensation

Below is a summary of compensation expense and unearned compensation (in millions):

																	Expected
																	period to
	Deferred Compensation												Unearned Compensation				recognize
	Expensed						Capitalized						As of		As of		unearned
	Year Ended December 31,												December 31,		December 31,		compensation
Type of incentive award	2023		2022		2021		2023		2022		2021		2023		2022		(in years)
Long-term incentive units	$	14.5	$	21.7	$	15.4	$	0.2	$	0.2	$	0.2	$	16.6	$	20.7	2.1
Performance-based awards		12.9		21.4		23.9		0.2		0.5		0.7		19.9		30.3	2.0
Service-based restricted stock units		21.1		25.9		23.2		7.5		5.4		3.3		66.4		55.4	2.5
Interxion awards		6.0		4.7		17.7		0.1		—		—		—		1.9	—

Schedule of weighted average fair value

	Weighted Average Fair Value at Date of Grant
Type of incentive award	2023		2022		2021
Long-term incentive units	$	121.99	$	146.37	$	132.66
Performance-based awards		97.06		154.26		137.69
Restricted stock		132.07		131.57		129.52

Summary of Long-Term Incentive Unit Activity

		Weighted-Average		Weighted-Average		Aggregate
		Grant Date Fair		Remaining Contractual		Intrinsic Value (1)
Unvested LTIP Units	Units	Value		Life (Years)		(in thousands)
Unvested, beginning of period	279,258	$	146.37
Granted	180,535		104.82
Vested	(181,182)		136.39
Cancelled or expired	(40,251)		149.36
Unvested, end of period	238,360	$	121.99		1.96	$	32,078

(1) The intrinsic value is calculated based on the market value of our common stock as of December 31, 2023.

Summary of Restricted Stock Activity

		Weighted-Average		Weighted-Average			Aggregate
		Grant Date Fair		Remaining Contractual			Intrinsic Value (1)
Unvested Restricted Stock Units	Shares	Value		Life (Years)			(in thousands)
Unvested, beginning of period	507,837	$	131.57
Granted	568,671		122.25
Vested	(371,232)		119.87
Cancelled or expired	(83,413)		116.39
Unvested, end of period	621,863	$	132.07		2.47	$		83,690

(1) The intrinsic value is calculated based on the market value of our common stock as of December 31, 2023.