Acquisitions and Dispositions - Acquired Entities (Details) - USD ($) $ in Millions			3 Months Ended	6 Months Ended	12 Months Ended
	Oct. 03, 2022	Jan. 31, 2022	Mar. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jul. 18, 2017
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Restricted cash			$ 401.8	$ 401.8	$ 438.5
Goodwill			1,459.2	1,459.2	1,450.9
NoteMachine
Business Acquisition [Line Items]
Acquisition date	Oct. 03, 2022
Percentage of shares acquired	100.00%
Annual revenues						$ 150.0
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Purchase consideration - cash paid				183.6
Contingent consideration	$ 10.1
Fair value of purchase consideration	193.7
Cash	6.8
Restricted cash	15.3
Accounts receivable	37.9
Other current assets	14.5
Property and equipment, net	39.9
Intangible assets	84.2
Goodwill	61.2
Other noncurrent assets	6.2
Current liabilities	(50.3)
Noncurrent liabilities	(22.0)
Fair value of net assets acquired	$ 193.7
NoteMachine | Europe
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill			60.0	60.0
NoteMachine | North America
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill			1.0	$ 1.0
NoteMachine | Customer relationships
Business Acquisition [Line Items]
Remaining Amortization Period	13 years
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets	$ 47.0
NoteMachine | Developed technology
Business Acquisition [Line Items]
Remaining Amortization Period	12 years
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets	$ 27.0
NoteMachine | Trade names
Business Acquisition [Line Items]
Remaining Amortization Period	5 years
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets	$ 10.0
Touchpoint 21 LLC
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Fair value of purchase consideration		$ 15.0
Maco
Business Acquisition [Line Items]
Percentage of shares acquired							100.00%
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Severance Costs			$ 3.3		$ 12.5