Earnings (Loss) per Share - Reconciliation of Weighted-Average Common Shares Outstanding (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Income (Loss) Attributable to Parent, Diluted [Abstract]
Net income (loss) attributable to PENN Entertainment, Inc.	$ (490.0)	$ 222.1	$ 420.8
Net income applicable to preferred stock	0.0	0.9	2.1
Net income (loss) applicable to common stock	$ (490.0)	$ 221.2	$ 418.7
Determination of shares:
Weighted-average common shares outstanding - basic (in shares)	152.1	161.2	158.7
Assumed conversion of convertible debt (in shares)	0.0	14.1	14.1
Weighted-average common shares outstanding—diluted (in shares)	152.1	176.6	175.5
Stock options
Determination of shares:
Assumed conversion of dilutive employee stock-based awards and restricted stock (in shares)	0.0	1.2	2.3
Restricted stock
Determination of shares:
Assumed conversion of dilutive employee stock-based awards and restricted stock (in shares)	0.0	0.1	0.4