Subsequent Event (Details)	12 Months Ended
Dec. 31, 2017 trading_day	Feb. 07, 2018 $ / shares
Subsequent Event [Line Items]
Number of average trading days' closing prices used to determine the purchase price of outstanding units of non-affiliates \| trading_day	20
Terra Nitrogen Company LP [Member] \| Terra Nitrogen GP Inc [Member] \| Subsequent Event
Subsequent Event [Line Items]
Business Acquisition, Share Price \| $ / shares		$ 84.033

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration