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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

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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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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3)

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.13,16)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13, 16

-Article 9

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The cash inflow from bank borrowing during the year.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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The cash inflow from other borrowing not otherwise defined in the taxonomy.

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The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 45

-Paragraph 15

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-Glossary Financing Activities

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The cash outflow for the payment of other borrowing not otherwise defined in the taxonomy.

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Value of investments transferred from the entity's investments in noncash transactions.

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Debt to capitalization ratios as per terms of revolver.

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No definition available.

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Reflects when the credit facility terminates, which is presented in month, year.

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No definition available.

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Maturity date of accounts receivable sales facility.

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Debt, Bank Debt and Credit Facilities (Details)	6 Months Ended						0 Months Ended			6 Months Ended		6 Months Ended						6 Months Ended
Debt, Bank Debt and Credit Facilities (Details)	Jun. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2013 A/R Sales Facility [Member] USD ($)	Jun. 30, 2012 A/R Sales Facility [Member] USD ($)	May 01, 2013 Spinoff [Member] USD ($)	Mar. 20, 2013 Spinoff [Member] USD ($)	May 01, 2013 Spinoff [Member] Notes Payable to Banks [Member] USD ($)	Apr. 16, 2013 Spinoff [Member] Sourced From Parent's Short-Term Borrowings [Member] Notes Payable to Banks [Member] USD ($)	Mar. 20, 2013 Revolving Credit Facility [Member] Spinoff [Member] USD ($)	Jun. 30, 2013 Letter of Credit [Member] USD ($)	Dec. 31, 2012 Letter of Credit [Member] USD ($)	Jun. 30, 2013 U S Revolver [Member] USD ($)	Jun. 30, 2012 U S Revolver [Member] USD ($)	Dec. 31, 2012 U S Revolver [Member] USD ($)	Jun. 30, 2013 U S Revolver [Member] Maximum [Member]	Jun. 30, 2013 U S Revolver Letter of Credit [Member] USD ($)	Dec. 31, 2012 U S Revolver Letter of Credit [Member] USD ($)	Jun. 30, 2013 Canadian Revolver [Member] CAD	Jun. 30, 2012 Canadian Revolver [Member] CAD	Dec. 31, 2012 Canadian Revolver [Member] CAD	Jun. 30, 2013 Canadian Revolver Letter of Credit [Member] CAD	Dec. 31, 2012 Canadian Revolver Letter of Credit [Member] CAD	Mar. 20, 2013 Line of Credit [Member] Spinoff [Member] USD ($)	Jun. 30, 2013 Other Letter of Credit [Member] USD ($)	Dec. 31, 2012 Other Letter of Credit [Member] USD ($)
Line of Credit Facility
Line of credit facility, maximum borrowing capacity			$ 1,500,000,000			$ 800,000,000			$ 300,000,000	$ 550,000,000		$ 3,000,000,000						50,000,000					$ 500,000,000
Line of credit facility, expiration date (month, year)										June 2014		December 2016						November 2013
Amount outstanding										250,000,000	418,000,000	0		0		59,000,000	59,000,000	0		0	9,000,000	10,000,000		87,000,000	275,000,000
Accounts Receivable Sales Facility
Balance as of beginning of period			100,000,000	250,000,000
Proceeds from the sale of receivables	0	1,300,000,000	0	1,300,000,000
Repayments	0	(1,450,000,000)	0	(1,450,000,000)
Balance as of end of period			100,000,000	100,000,000
Credit Facilities (Textual)
Debt to capitalization ratios as per terms of revolver												0.19		0.23	0.60
Borrowings from long-term lines of credit	0	1,100,000,000										0	1,100,000,000					0	0
Repayments of long-term lines of credit	0	1,100,000,000										0	1,100,000,000					0	0
Proceeds from short-term debt	550,000,000	0						550,000,000
Senior unsecured bonds of CST issued to us					550,000,000
CST bonds exchanged in settlement of short-term borrowings							$ 550,000,000
Accounts Receivable Sales Facility (Textual)
Maturity date of accounts receivable sales facility			July 2014