Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Property, plant and equipment of TRIP Holdings	$ 5,479.3	$ 5,407.9
Accumulated depreciation on property, plant and equipment of TRIP Holdings	1,262.0	1,228.4
Restricted cash of TRIP Holdings	224.0	240.3
Debt unamortized discount	96.8	99.8
Preferred stock, shares authorized	1.5	1.5
Preferred stock, shares unissued	1.5	1.5
Common stock, shares authorized	200.0	200.0
TRIP Holdings [Member]
Property, plant and equipment of TRIP Holdings	1,271.4	1,257.7
Accumulated depreciation on property, plant and equipment of TRIP Holdings	128.7	122.7
Restricted cash of TRIP Holdings	59.2	74.6
Debt unamortized discount	$ 96.8	$ 99.8

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

The number of nonredeemable preferred stock (shares) (or preferred stock redeemable solely at the option of the issuer) allocated to investors to buy shares of a new issue of preferred stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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- Definition

Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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