CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 1,758.0	$ 1,755.4
Short-term investments	11.6	17.9
Accounts receivable, net of allowances of $30.0 in 2012 and $28.0 in 2011	637.2	621.8
Deferred tax assets, net	32.1	38.7
Other current assets	81.4	91.9
Total current assets	2,520.3	2,525.7
Property and equipment, net of accumulated depreciation of $286.6 in 2012 and $258.2 in 2011	296.1	307.1
Goodwill	623.8	637.1
Intangible assets, net	212.7	226.5
Deferred tax assets, net	158.2	168.5
Other assets	100.1	96.0
Total assets	3,911.2	3,960.9
Current liabilities:
Accounts payable and accrued liabilities	355.1	555.3
Unrecognized tax benefits	0	0
Current portion of long-term debt	31.9	63.8
Deferred revenue	626.4	545.8
Total current liabilities	1,013.4	1,164.9
Non-current portion of deferred revenue	102.8	94.9
Long-term debt	1,610.2	1,607.4
Deferred tax liabilities, net	55.9	58.1
Unrecognized tax benefits	167.2	156.6
Other liabilities	421.5	410.1
Total liabilities	3,371.0	3,492.0
Contingencies (Note 14)
Redeemable noncontrolling interest	75.3	72.3
Shareholders' equity(deficit):
Preferred stock, par value $.01 per share; 10,000,000 shares authorized; no shares issued and outstanding	0	0
Capital surplus	342.8	365.1
Retained earnings	4,902.2	4,713.3
Treasury stock, at cost; 120,619,040 and 120,462,232 shares of common stock at June 30, 2012 and December 31, 2011, respectively	(4,652.5)	(4,614.5)
Accumulated other comprehensive loss	(138.8)	(82.1)
Total Moody's shareholders' equity (deficit)	457.1	385.2
Noncontrolling interests	7.8	11.4
Total shareholders' equity (deficit)	464.9	396.6
Total liabilities, redeemable noncontrolling interest and shareholders' equity (deficit)	3,911.2	3,960.9
Nonvoting Common Stock [Member]
Shareholders' equity(deficit):
Common stock	0	0
Common Stock [Member]
Shareholders' equity(deficit):
Common stock	$ 3.4	$ 3.4