Debt (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Schedule of Carrying Amount and Fair Value of Long-term Debt Instruments

Long-term debt is as follows:

	DECEMBER 31, 2023								DECEMBER 31, 2022
	DEBT (INCLUSIVE OF DISCOUNT)		UNAMORTIZED DEFERRED FINANCING COSTS		CARRYING AMOUNT		FAIR VALUE		DEBT (INCLUSIVE OF DISCOUNT)		UNAMORTIZED DEFERRED FINANCING COSTS		CARRYING AMOUNT		FAIR VALUE
Revolving Credit Facility(1)	$	—	$	(4,621)	$	(4,621)	$	—	$	1,072,200	$	(6,790)	$	1,065,410	$	1,072,200
Term Loan A(1)	228,125		—		228,125		228,125		240,625		—		240,625		240,625
Term Loan B due 2026(1)(2)	659,298		(2,498)		656,800		659,750		666,073		(3,747)		662,326		666,750
Term Loan B due 2031(1)(3)	1,191,000		(13,026)		1,177,974		1,200,000		—		—		—		—
Virginia 3 Term Loans(5)	101,218		(4,641)		96,577		101,218		—		—		—		—
Virginia 4/5 Term Loans(5)	16,338		(5,892)		10,446		16,338		—		—		—		—
Australian Dollar Term Loan (4)(5)	197,743		(482)		197,261		199,195		202,641		(633)		202,008		204,623
UK Bilateral Revolving Credit Facility(5)	178,239		—		178,239		178,239		169,361		—		169,361		169,361
37/8% GBP Senior Notes due 2025 (the "GBP Notes")(6)(8)(9)	509,254		(1,763)		507,491		489,108		483,888		(2,589)		481,299		445,206
47/8% Senior Notes due 2027 (the “47/8% Notes due 2027")(6)(7)(8)	1,000,000		(5,332)		994,668		967,500		1,000,000		(6,754)		993,246		917,500
51/4% Senior Notes due 2028 (the “51/4% Notes due 2028")(6)(7)(8)	825,000		(5,019)		819,981		800,250		825,000		(6,200)		818,800		754,875
5% Senior Notes due 2028 (the “5% Notes due 2028")(6)(7)(8)	500,000		(3,316)		496,684		478,750		500,000		(4,039)		495,961		450,000
7% Senior Notes due 2029 (the "7% Notes due 2029")(6)(7)(8)	1,000,000		(10,813)		989,187		1,027,500		—		—		—		—
47/8% Senior Notes due 2029 (the “47/8% Notes due 2029")(6)(7)(8)	1,000,000		(8,318)		991,682		945,000		1,000,000		(9,764)		990,236		865,000
51/4% Senior Notes due 2030 (the “51/4% Notes due 2030")(6)(7)(8)	1,300,000		(9,903)		1,290,097		1,241,500		1,300,000		(11,407)		1,288,593		1,111,500
41/2% Senior Notes due 2031 (the “41/2% Notes")(6)(7)(8)	1,100,000		(8,917)		1,091,083		995,500		1,100,000		(10,161)		1,089,839		891,000
5% Senior Notes due 2032 (the “5% Notes due 2032")(6)(8)(10)	750,000		(11,206)		738,794		684,375		750,000		(12,511)		737,489		622,500
55/8% Senior Notes due 2032 (the “55/8% Notes")(6)(7)(8)	600,000		(4,985)		595,015		567,000		600,000		(5,566)		594,434		520,500
Real Estate Mortgages, Financing Lease Liabilities and Other(11)	519,907		(403)		519,504		519,907		425,777		(578)		425,199		425,777
Accounts Receivable Securitization Program(12)	358,500		(317)		358,183		358,183		314,700		(531)		314,169		314,700
Total Long-term Debt	12,034,622		(101,452)		11,933,170				10,650,265		(81,270)		10,568,995
Less Current Portion	(120,670)		—		(120,670)				(87,546)		—		(87,546)
Long-term Debt, Net of Current Portion	$	11,913,952	$	(101,452)	$	11,812,500			$	10,562,719	$	(81,270)	$	10,481,449

(1)The capital stock or other equity interests of our United States subsidiaries representing the substantial majority of our United States operations, and up to 66% of the capital stock or other equity interests of most of our first-tier foreign subsidiaries, are pledged to secure these debt instruments, together with all intercompany obligations (including promissory notes) of subsidiaries owed to us or to one of our United States subsidiary guarantors. In addition, Iron Mountain Canada Operations ULC has pledged 66% of the capital stock of its subsidiaries, and all intercompany obligations (including promissory notes) owed to or held by it, to secure the Revolving Credit Facility. The fair value (Level 2 and Level 3 of fair value hierarchy described at Note 2.p.) of these debt instruments approximates the carrying value (as borrowings under these debt instruments are based on current variable market interest rates (plus a margin that is subject to change based on our consolidated leverage ratio), as of December 31, 2023 and 2022 (collectively, the “Credit Agreement Collateral”).

(2)The amount of debt for the Term Loan B due 2026 (as defined below) reflects an unamortized original issue discount of $452 and $677 as of December 31, 2023 and 2022, respectively.

(3)The amount of debt for the Term Loan B due 2031 (as defined below) reflects an unamortized original issue discount of $9,000 as of December 31, 2023.

(4)The amount of debt for the AUD Term Loan reflects an unamortized original issue discount of $1,452 and $1,982 as of December 31, 2023 and 2022, respectively.

(5)The fair value (Level 2 of fair value hierarchy described at Note 2.p.) of this debt instrument approximates the carrying value as borrowings under this debt instrument are based on a current variable market interest rate.

(6)The fair values (Level 2 of fair value hierarchy described at Note 2.p.) of these debt instruments are based on quoted market prices for comparable notes on December 31, 2023 and 2022, respectively.

(7)Collectively, the "Parent Notes". IMI is the direct obligor on the Parent Notes, which are fully and unconditionally guaranteed, on a senior basis, by IMI’s United States subsidiaries that represent the substantial majority of our United States operations (the "Note Guarantors"). These guarantees are joint and several obligations of the Note Guarantors. The remainder of our subsidiaries do not guarantee the Parent Notes.

(8)Collectively, the "Unregistered Notes". The Unregistered Notes have not been registered under the Securities Act of 1933, as amended (the "Securities Act"), or under the securities laws of any other jurisdiction. Unless they are registered, the Unregistered Notes may be offered only in transactions that are exempt from registration under the Securities Act or the securities laws of any other jurisdiction.

(9)Iron Mountain (UK) PLC ("IM UK") is the direct obligor on the GBP Notes, which are fully and unconditionally guaranteed, on a senior basis, by IMI and the Note Guarantors. These guarantees are joint and several obligations of IMI and the Note Guarantors. The remainder of our subsidiaries do not guarantee the GBP Notes.

(10)Iron Mountain Information Management Services, Inc. ("IMIM Services") is the direct obligor on the 5% Notes due 2032, which are fully and unconditionally guaranteed, on a senior basis, by IMI and the Note Guarantors. These guarantees are joint and several obligations of IMI and the Note Guarantors. The remainder of our subsidiaries do not guarantee the 5% Notes due 2032.

(11)We believe the fair value (Level 2 of fair value hierarchy described at Note 2.p.) of this debt approximates its carrying value as these borrowings are based on current market interest rates. This debt includes the following:

	DECEMBER 31, 2023		DECEMBER 31, 2022
Real estate mortgages(1)	$	57,753	$	58,355
Financing lease liabilities(2)	349,865		332,905
Other notes and other obligations(3)	112,289		34,517
	$	519,907	$	425,777

(1)Bear interest at approximately 3.6% at both December 31, 2023 and 2022, and includes $50,000 outstanding under our Mortgage Securitization Program at both December 31, 2023 and 2022.

(2)Bear a weighted average interest rate of 6.1% and 5.2% at December 31, 2023 and 2022.

(3)These notes and other obligations, which were assumed by us as a result of certain acquisitions bear a weighted average interest rate of 8.5% and 10.1% at December 31, 2023 and 2022.

(12) The Accounts Receivable Securitization Special Purpose Subsidiaries are the obligors under this program. We believe the fair value (Level 2 of fair value hierarchy described at Note 2.p.) of this debt approximates its carrying value as borrowings under this debt instrument are based on a current variable market interest rate.

On May 15, 2023, IMI completed a private offering of:

SERIES OF NOTES	AGGREGATE PRINCIPAL AMOUNT
7% Notes due 2029	$	1,000,000

Schedule of Redemption Dates and Prices of the Senior or Senior Subordinated Notes

The key terms of our indentures are as follows:

SENIOR NOTES	AGGREGATE PRINCIPAL AMOUNT		DIRECT OBLIGOR	MATURITY DATE	CONTRACTUAL INTEREST RATE	INTEREST PAYMENTS DUE	PAR CALL DATE(1)
GBP Notes	£	400,000	IM UK	November 15, 2025	37/8%	May 15 and November 15	November 15, 2022
47/8% Notes due 2027	$	1,000,000	IMI	September 15, 2027	47/8%	March 15 and September 15	September 15, 2025
51/4% Notes due 2028	$	825,000	IMI	March 15, 2028	51/4%	March 15 and September 15	March 15, 2025
5% Notes due 2028	$	500,000	IMI	July 15, 2028	5%	January 15 and July 15	July 15, 2025
7% Notes due 2029	$	1,000,000	IMI	February 15, 2029	7%	February 15 and August 15	August 15, 2025
47/8% Notes due 2029	$	1,000,000	IMI	September 15, 2029	47/8%	March 15 and September 15	September 15, 2027
51/4% Notes due 2030	$	1,300,000	IMI	July 15, 2030	51/4%	January 15 and July 15	July 15, 2028
41/2% Notes	$	1,100,000	IMI	February 15, 2031	41/2%	February 15 and August 15	February 15, 2029
5% Notes due 2032	$	750,000	IMIM Services	July 15, 2032	5%	May 15 and November 15	July 15, 2027
55/8% Notes	$	600,000	IMI	July 15, 2032	55/8%	January 15 and July 15	July 15, 2029

(1)We may redeem the notes at any time, at our option, in whole or in part. Prior to the par call date, we may redeem the notes at the redemption price or make-whole premium specified in the applicable indenture, together with accrued and unpaid interest to, but excluding, the redemption date. On or after the par call date, we may redeem the notes at a price equal to 100% of the principal amount being redeemed, together with accrued and unpaid interest to, but excluding, the redemption date.

Schedule of Maturities of Long-term Debt

MATURITIES OF LONG-TERM DEBT (GROSS OF DISCOUNTS) ARE AS FOLLOWS:

YEAR	AMOUNT
2024	$	120,670
2025	1,221,903
2026	1,055,120
2027	1,238,920
2028	1,393,004
Thereafter	7,015,909
	12,045,526
Net Discounts	(10,904)
Net Deferred Financing Costs	(101,452)
Total Long-term Debt (including current portion)	$	11,933,170