Consolidating Guarantor Financial Information (Schedule of Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 553	$ 417
Investing Activities
Capital expenditures on property, plant and equipment	(117)	(130)
Acquisitions, net of cash acquired	(3)	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	(210)	(143)
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	0	0
Other, net	(24)	(10)
Net cash provided by (used in) investing activities	(354)	(283)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(2)	1
Proceeds from short-term borrowings	26	25
Repayments of short-term borrowings	(39)	(43)
Proceeds from long-term debt	0	0
Repayments of long-term debt	(12)	(13)
Purchases of treasury stock, including related fees	0	(103)
Dividends to parent	0	0
Contributions from parent	0	0
Stock option exercises	2	3
Series A common stock dividends	(84)	(67)
Return of capital to parent	0	0
Contributions from noncontrolling interests	155	148
Other, net	(11)	(1)
Net cash provided by (used in) financing activities	35	(50)
Exchange rate effects on cash and cash equivalents	(26)	(4)
Net increase (decrease) in cash and cash equivalents	208	80
Cash and cash equivalents as of beginning of period	780	984
Cash and cash equivalents as of end of period	988	1,064
Parent Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	83	169
Investing Activities
Capital expenditures on property, plant and equipment	0	0
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	0	0
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	0	0
Other, net	0	0
Net cash provided by (used in) investing activities	0	0
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	0	0
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	0	0
Repayments of long-term debt	0	0
Purchases of treasury stock, including related fees	0	(103)
Dividends to parent	0	0
Contributions from parent	0	0
Stock option exercises	2	3
Series A common stock dividends	(84)	(67)
Return of capital to parent	0	0
Contributions from noncontrolling interests	0	0
Other, net	0	0
Net cash provided by (used in) financing activities	(82)	(167)
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	1	2
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	1	2
Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	45	109
Investing Activities
Capital expenditures on property, plant and equipment	0	0
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	0	0
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	3	3
Other, net	0	0
Net cash provided by (used in) investing activities	3	3
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	25	61
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	15	0
Repayments of long-term debt	(5)	(5)
Purchases of treasury stock, including related fees	0	0
Dividends to parent	(83)	(168)
Contributions from parent	0	0
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	0	0
Contributions from noncontrolling interests	0	0
Other, net	0	0
Net cash provided by (used in) financing activities	(48)	(112)
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	0	0
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	285	333
Investing Activities
Capital expenditures on property, plant and equipment	(74)	(100)
Acquisitions, net of cash acquired	(3)	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	(9)	(34)
Return of capital from subsidiary	0	51
Contributions to subsidiary	(60)	(97)
Intercompany loan receipts (disbursements)	(25)	(61)
Other, net	(12)	(6)
Net cash provided by (used in) investing activities	(183)	(247)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(1)	10
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	0	0
Repayments of long-term debt	(3)	(3)
Purchases of treasury stock, including related fees	0	0
Dividends to parent	(83)	(168)
Contributions from parent	0	0
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	0	0
Contributions from noncontrolling interests	0	0
Other, net	(10)	(1)
Net cash provided by (used in) financing activities	(97)	(162)
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	5	(76)
Cash and cash equivalents as of beginning of period	110	284
Cash and cash equivalents as of end of period	115	208
Non-Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	306	142
Investing Activities
Capital expenditures on property, plant and equipment	(43)	(30)
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	(201)	(109)
Return of capital from subsidiary	0	0
Contributions to subsidiary	0	0
Intercompany loan receipts (disbursements)	(15)	0
Other, net	(12)	(4)
Net cash provided by (used in) investing activities	(271)	(143)
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(1)	(9)
Proceeds from short-term borrowings	26	25
Repayments of short-term borrowings	(39)	(43)
Proceeds from long-term debt	0	0
Repayments of long-term debt	(7)	(8)
Purchases of treasury stock, including related fees	0	0
Dividends to parent	0	0
Contributions from parent	60	97
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	0	(51)
Contributions from noncontrolling interests	155	148
Other, net	(1)	0
Net cash provided by (used in) financing activities	193	159
Exchange rate effects on cash and cash equivalents	(26)	(4)
Net increase (decrease) in cash and cash equivalents	202	154
Cash and cash equivalents as of beginning of period	670	700
Cash and cash equivalents as of end of period	872	854
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(166)	(336)
Investing Activities
Capital expenditures on property, plant and equipment	0	0
Acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses and assets, net	0	0
Capital expenditures related to Fairway Methanol LLC	0	0
Return of capital from subsidiary	0	(51)
Contributions to subsidiary	60	97
Intercompany loan receipts (disbursements)	37	58
Other, net	0	0
Net cash provided by (used in) investing activities	97	104
Financing Activities
Net change in short-term borrowings with maturities of 3 months or less	(25)	(61)
Proceeds from short-term borrowings	0	0
Repayments of short-term borrowings	0	0
Proceeds from long-term debt	(15)	0
Repayments of long-term debt	3	3
Purchases of treasury stock, including related fees	0	0
Dividends to parent	166	336
Contributions from parent	(60)	(97)
Stock option exercises	0	0
Series A common stock dividends	0	0
Return of capital to parent	0	51
Contributions from noncontrolling interests	0	0
Other, net	0	0
Net cash provided by (used in) financing activities	69	232
Exchange rate effects on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	$ 0	$ 0