Financial Instruments - Schedule of Estimated Fair Value of Partnership's Financial Instruments on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Other:
Long-term debt (note 10)	$ (1,413,353)	$ (1,315,231)
Carrying Amount Asset (Liability) [Member]
Other:
Advances to joint venture partner (note 8)	14,004	10,200
Carrying Amount Asset (Liability) [Member] \| Level 1 [Member]
Recurring:
Cash and cash equivalents and restricted cash	642,166	589,261
Carrying Amount Asset (Liability) [Member] \| Level 2 [Member] \| Interest rate swap agreements [Member]
Derivative instruments (note 13)
Interest rate swap agreements - assets	165,687	159,603
Interest rate swap agreements - liabilities	(304,220)	(304,066)
Carrying Amount Asset (Liability) [Member] \| Level 2 [Member] \| Cross currency swap agreement [Member]
Derivative instruments (note 13)
Cross currency swap agreement	(2,623)
Carrying Amount Asset (Liability) [Member] \| Level 3 [Member]
Derivative instruments (note 13)
Other derivative	1,100	(600)
Carrying Amount Asset (Liability) [Member] \| Public [Member] \| Level 1 [Member]
Other:
Long-term debt (note 10)	(125,791)
Carrying Amount Asset (Liability) [Member] \| Private [Member] \| Level 2 [Member]
Other:
Long-term debt (note 10)	(1,287,562)	(1,315,231)
Fair Value Asset (Liability) [Member] \| Level 1 [Member]
Recurring:
Cash and cash equivalents and restricted cash	642,166	589,261
Fair Value Asset (Liability) [Member] \| Level 2 [Member] \| Interest rate swap agreements [Member]
Derivative instruments (note 13)
Interest rate swap agreements - assets	165,687	159,603
Interest rate swap agreements - liabilities	(304,220)	(304,066)
Fair Value Asset (Liability) [Member] \| Level 2 [Member] \| Cross currency swap agreement [Member]
Derivative instruments (note 13)
Cross currency swap agreement	(2,623)
Fair Value Asset (Liability) [Member] \| Level 3 [Member]
Derivative instruments (note 13)
Other derivative	1,100	(600)
Fair Value Asset (Liability) [Member] \| Public [Member] \| Level 1 [Member]
Other:
Long-term debt (note 10)	(129,439)
Fair Value Asset (Liability) [Member] \| Private [Member] \| Level 2 [Member]
Other:
Long-term debt (note 10)	$ (1,170,788)	$ (1,191,117)

Unsecured advances to and from joint venture partners.

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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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