Stockholders' Equity - eXponential Stock Performance Plan (Details) $ in Millions			1 Months Ended	12 Months Ended
	Feb. 12, 2019	May 24, 2018 USD ($) shares	Jan. 31, 2019 shares	Dec. 31, 2019 USD ($) tranche shares	Dec. 31, 2018 shares	Dec. 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
New option granted (in shares) | shares				0	0	0
First tranche		$ 2,500.0
Incremental increase		$ 1,000.0
Stock based compensation expense				$ 37.4
Number of Options expected to vest | shares				4,800,000
Weighted average period				6 years
eXponential Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units, granted (in shares) | shares			60
Stock based compensation expense				$ 17.5
eXponential Stock Units | 2019 eXponential Stock Performance Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock, expiration period	9 years
Number of vesting tranches of share-based awards | tranche				12
New option granted (in shares) | shares				5,900,000
First tranche				$ 2,500.0
Incremental increase				1,000.0
Stock based compensation expense				$ 17.5
Number of Options expected to vest | shares				4,200,000
Total unrecognized stock-based compensation expense for operational goals				$ 139.8
Unrecognized stock-based compensation expense				$ 35.9
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
New option granted (in shares) | shares		6,365,856
Weighted average period				5 years 10 months 24 days