Summary of Significant Accounting Policies (Details 6) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 year fund bank	Mar. 31, 2011	Dec. 31, 2011 fund bank
Income (Loss) Per Share-Basic and Diluted
Income (Loss) from Continuing Operations	$ 61,073	$ 81,176
Total income (Loss) from discontinued operations (see Note 10)	(5,093)	(6,557)
Net Income (Loss) Attributable to Iron Mountain Incorporated	55,350	73,460
Weighted-average shares-basic	171,320,000	200,228,000
Effect of dilutive potential stock options (in shares)	720,788	995,149
Effect of dilutive potential restricted stock, RSUs and PUs (in shares)	181,867	27,659
Weighted-average shares-diluted	172,223,000	201,251,000
Earnings (Losses) per share-basic:
Income (Loss) from continuing operations (in dollars per share)	$ 0.36	$ 0.41
Total income (Loss) from Discontinued Operations (see Note 10) (in dollars per share)	$ (0.03)	$ (0.03)
Net Income (Loss) Attributable to Iron Mountain Incorporated (in dollars per share)	$ 0.32	$ 0.37
Earnings (Losses) per share-diluted:
Income (Loss) from continuing operations (in dollars per share)	$ 0.35	$ 0.40
Total income (Loss) from Discontinued Operations (see Note 10) (in dollars per share)	$ (0.03)	$ (0.03)
Net Income (Loss) Attributable to Iron Mountain Incorporated (in dollars per share)	$ 0.32	$ 0.37
Antidilutive stock options, RSUs and PUs, excluded from the calculation (in shares)	2,045,616	8,701,049
Allowance for Doubtful Accounts and Credit Memo Reserves
The general period to charge-off uncollectible balances of receivable, as circumstances warrant, is no later than this period of time past due (in years)	1
Income Taxes:
Effective tax rates (as a percent)	29.30%	17.10%
Statutory income tax rate (as a percent)	35.00%	35.00%
Reduction in effective income tax rate reconciliation, other adjustments (as a percent)		12.60%
Reduction in effective tax rate due to settlements with tax authorities (as a percent)	8.90%	2.00%
Reduction in gross interest and penalties recorded	249	609
Accrued interest and penalties recorded	2,570		2,819
Undistributed earning of foreign subsidiaries	75,000
Concentrations of Credit Risk
Number of global banks with cash, cash equivalent and restricted cash held on deposit	5		5
Number of "Triple A" rated money market funds with cash, cash equivalent and restricted cash held on deposit	1		1
Maximum investment limit in any one mutual fund or financial institution	50,000
Cash, cash equivalent and restricted cash	213,405		214,955
Money market fund and time deposits	$ 166,343		$ 181,823