Earnings (Loss) per Share - Reconciliation of Weighted-Average Common Shares Outstanding (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Income (Loss) Attributable to Parent, Diluted [Abstract]
Net income (loss) attributable to Penn National	$ 420.8	$ (669.5)	$ 43.9
Net income applicable to preferred stock	2.1	0.0	0.0
Net income (loss) applicable to common stock	$ 418.7	$ (669.5)	$ 43.9
Determination of shares:
Weighted-average common shares outstanding - basic (in shares)	158.7	134.0	115.7
Assumed conversion of convertible debt (in shares)	14.1	0.0	0.0
Weighted-average common shares outstanding—Diluted (in shares)	175.5	134.0	117.8
Stock options
Determination of shares:
Assumed conversion of dilutive employee stock-based awards and restricted stock (in shares)	2.3	0.0	1.8
Restricted stock
Determination of shares:
Assumed conversion of dilutive employee stock-based awards and restricted stock (in shares)	0.4	0.0	0.3