Redeemable Series A Preferred Units - Summary of Issuances of Series A Preferred Units (Details) - USD ($)	1 Months Ended	12 Months Ended
Oct. 31, 2017	Aug. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	May 31, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Temporary Equity Disclosure [Abstract]
Issuance of preferred units through private placements	1,750,000	2,000,000	1,613,100	700,000	1,000,000	1,386,900	1,000,000	9,450,000	4,086,900
Purchase Price	$ 17,500,000	$ 20,000,000	$ 16,131,000	$ 7,000,000	$ 10,000,000	$ 13,869,000	$ 10,000,000	$ 94,500,000	$ 40,869,000
Distribution Rate	3.00%	3.00%	3.00%	3.00%	3.00%	3.00%	3.00%
Redemption Price per Unit	$ 10.00	$ 10.00	$ 10.00	$ 10.00	$ 10.00	$ 10.00	$ 10.00		$ 10.00
Earliest Redemption Date	2023-10	2023-08	2023-03	2022-12	2022-09	2022-05	2022-03

Percentage of non-cumulative cash dividend.

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- Definition

Temporary equity redemption date.

+ References

No definition available.

+ Details

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- Definition

Monetary value of the issuance of new units of limited partnership interest in a private placement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

The number of units sold in a private placement of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

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- References

No definition available.

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- Definition

Amount to be paid per share that is classified as temporary equity by entity upon redemption. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=65877616&loc=d3e177068-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (27)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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