Accounts Receivable Securitization Facility Prior To Amendment

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- Definition

-- None. No documentation exists for this element. --

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- Definition

Coupon rate for semi-annually payment of interest for notes.

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- Definition

-- None. No documentation exists for this element. --

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New accounts receivable securitization facility.

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- Definition

Notes conversion rate for notes.

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- Definition

Per principal amount of notes for initial conversion rate

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- Definition

Servicing Fees Paid For Accounts Receivable Facility

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- Definition

The component of interest expense representing the noncash expenses charged against earnings in the period to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate caption: Noncash Interest Expense.

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The price per share of the conversion feature embedded in the debt instrument.

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The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

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Interest expense related to convertible debt instruments which has been recognized for the period, including the contractual interest coupon and amortization of the debt discount, if any.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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Amount of the required periodic payments applied to interest.

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

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Amount borrowed under the credit facility as of the balance sheet date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of long-term debt outstanding by type or by instrument at that time.

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The dollar amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Notes Payable and Long-Term Debt (Details) (USD $) In Millions, except Share data, unless otherwise specified										3 Months Ended			6 Months Ended		12 Months Ended			6 Months Ended		6 Months Ended		6 Months Ended		6 Months Ended
	Jun. 30, 2011	Dec. 31, 2010	Mar. 31, 2010	Jun. 30, 2011 Short Term Borrowings [Member]	Dec. 31, 2010 Short Term Borrowings [Member]	Jun. 30, 2011 Receivables Securitization [Member]	Dec. 31, 2010 Receivables Securitization [Member]	Jun. 30, 2011 Total Short Term Debt [Member]	Dec. 31, 2010 Total Short Term Debt [Member]	Jun. 30, 2011 3.50 % Convertible Notes [Member]	Mar. 31, 2011 3.50 % Convertible Notes [Member]	Jun. 30, 2010 3.50 % Convertible Notes [Member]	Jun. 30, 2011 3.50 % Convertible Notes [Member]	Jun. 30, 2010 3.50 % Convertible Notes [Member]	Dec. 31, 2010 3.50 % Convertible Notes [Member]	Sep. 08, 2010 3.50 % Convertible Notes [Member]	Apr. 09, 2009 3.50 % Convertible Notes [Member]	Jun. 30, 2011 5.75% Senior Notes [Member]	Dec. 31, 2010 5.75% Senior Notes [Member]	Jun. 30, 2011 8.00% Senior Notes [Member]	Dec. 31, 2010 8.00% Senior Notes [Member]	Jun. 30, 2011 4.625% Senior Notes [Member]	Dec. 31, 2010 4.625% Senior Notes [Member]	Jun. 30, 2011 7.125% Senior Notes [Member]	Dec. 31, 2010 7.125% Senior Notes [Member]	Jun. 30, 2011 Multi Currency Revolving Credit Facility [Member]	Dec. 31, 2010 Multi Currency Revolving Credit Facility [Member]	Mar. 31, 2010 Multi Currency Revolving Credit Facility [Member]	Jun. 30, 2011 Term Loan Facilities And Other [Member]	Dec. 31, 2010 Term Loan Facilities And Other [Member]	Jun. 30, 2011 Unamortized portion of debt derivative [Member]	Dec. 31, 2010 Unamortized portion of debt derivative [Member]
Short-term debt
Short-term Borrowings				$ 85.8	$ 42.4	$ 80.0	$ 80.0	$ 165.8	$ 122.4
Long-term debt
Long-term Debt	1,283.1	1,058.0								358.3			358.3		348.5			149.4	149.4	133.9	133.9	247.7	247.5	119.3	119.3	225.0	0		23.6	31.6	25.9	27.8
Current portion of long-term debt	363.6	6.1
Long-term debt, net of current portion	919.5	1,051.9
Debt instrument par value																		150		134		250		121
Debt instrument interest rate	3.50%		3.50%							3.50%			3.50%					5.75%		8.00%		4.625%		7.125%
Debt instrument maturity date													Apr. 15, 2012					Nov. 01, 2016		Oct. 01, 2019		Sep. 15, 2020		Feb. 15, 2029
Long-term Debt, Weighted Average Interest Rate	5.70%	6.40%
Current multi-currency revolving credit facility																										650.0		550.0
Multi-currency revolving credit facility at most																										1,000		600
Accounts Receivable Securitization Facility Prior To Amendment																50.0
New accounts receivable securitization facility																80.0
Servicing Fees Paid For Accounts Receivable Facility										0.3		0.3	0.7	0.5
Issuance Of Convertible Senior Notes																	373.8
Increase in capital in excess of par										36.5			36.5
Effective interest rate of convertible senior notes										9.365%			9.365%
Interest expense										8.3		7.8	16.3	15.4
Amortization of Debt Discount (Premium)										5.0		4.5	9.8	8.9
Semi-annually payment of interest for notes											6.5
Coupon rate for semi-annually payment of interest for notes											0.035
Per principal amount of notes for initial conversion rate										1,000.0			1,000.0
Initial conversion rate for notes										30.4706			30.4706
Debt instrument conversion price										$ 32.82			$ 32.82
Debt Instrument, Convertible, If-converted Value in Excess of Principal													546.3		450.2
Conversion premium										27.50%			27.50%
BorgWarner Inc. stock price - April 6, 2009										$ 25.74			$ 25.74
Bond hedge overlay at a net pre-tax cost										25.2			25.2
Conversion premium after bond hedge overlay										50.00%			50.00%
Conversion price per share after bond hedge overlay										$ 38.61			$ 38.61
Estimated fair value of senior unsecured notes	1,591.0	1,482.3
Fair value higher than carrying value for senior unsecured notes	582.4	483.7
Outstanding letter of credit	$ 50.0	$ 26.5