Debt (Tables)

3 Months Ended

Mar. 31, 2022

Debt Disclosure [Abstract]

Schedule of Debt Instruments

Debt at March 31, 2022 and December 31, 2021 was as follows (in millions): 

	March 31, 2022		December 31, 2021
Allegheny Technologies 5.875% Notes due 2027	350.0		350.0
Allegheny Technologies 5.125% Notes due 2031	350.0		350.0
Allegheny Technologies 4.875% Notes due 2029	325.0		325.0
Allegheny Technologies 3.5% Convertible Senior Notes due 2025	291.4		291.4
Allegheny Technologies 4.75% Convertible Senior Notes due 2022	84.2		84.2
Allegheny Ludlum 6.95% Debentures due 2025 (a)	150.0		150.0
Term Loan due 2024	200.0		200.0
U.S. revolving credit facility	—		—
Foreign credit facilities	12.7		27.4
Finance leases and other	80.7		85.7
Debt issuance costs	(19.9)		(20.8)
Debt	1,824.1		1,842.9
Short-term debt and current portion of long-term debt	116.7		131.3
Long-term debt	$	1,707.4	$	1,711.6

(a) The payment obligations of these debentures issued by Allegheny Ludlum, LLC are fully and unconditionally guaranteed by ATI.

Interest Income and Interest Expense Disclosure

Interest expense on the 2025 Convertible Notes was as follows:

	Three months ended March 31,
(in millions)	2022		2021
Contractual coupon rate	$	2.5	$	2.5
Amortization of debt issuance costs	0.4		0.4
Total interest expense	$	2.9	$	2.9

Interest expense on the 2022 Convertible Notes was as follows:

	Three months ended March 31,
(in millions)	2022		2021
Contractual coupon rate	$	1.0	$	1.0
Amortization of debt issuance costs	0.1		0.1
Total interest expense	$	1.1	$	1.1