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Partners' Equity (Details) $ / shares in Units, $ in Thousands | 1 Months Ended | 7 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 23, 2017 shares | Jul. 20, 2015 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($) shares | Dec. 31, 2015 USD ($) shares
Related Party Transaction |  |  |  |  |
Common unitholders - units issued | shares |  |  | 35,490,000 | 20,505,000 |
Common unitholders - units outstanding | shares |  |  | 35,490,000 | 20,505,000 |
Series A Preferred Units issued | shares |  |  | 3,000,000 | 3,000,000 |
Series A Preferred Units outstanding | shares |  |  | 3,000,000 | 3,000,000 |
General Partner unitholders - units issued | shares |  |  | 35,526 | 35,526 |
General Partner unitholders - units outstanding | shares |  |  | 35,526 | 35,526 |
Issuance of Series A preferred units, net of issuance costs paid |  |  | $ 0 | $ 0 | $ 72,446
Total distributions paid to all classes of unitholders |  |  | $ 66,857 | 66,856 | 62,207
Distribution 4 - FY 2016 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Declaration Date |  |  | Jan. 01, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.4225 |  |
Total distributions paid to all classes of unitholders |  |  | $ 15,000 |  |
Distributions per unit declared - distribution date |  |  | Jan. 19, 2017 |  |
Distributions per unit declared - record date |  |  | Jan. 11, 2017 |  |
Distribution 1 - FY 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Announcement Date |  |  | Apr. 12, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.4225 |  |
Total distributions paid to all classes of unitholders |  |  | $ 15,000 |  |
Distributions per unit declared - distribution date |  |  | Apr. 28, 2017 |  |
Distributions per unit declared - record date |  |  | Apr. 21, 2017 |  |
Distribution 2 - FY 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Declaration Date |  |  | Jul. 01, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.4225 |  |
Total distributions paid to all classes of unitholders |  |  | $ 15,000 |  |
Distributions per unit declared - distribution date |  |  | Jul. 18, 2017 |  |
Distributions per unit declared - record date |  |  | Jul. 11, 2017 |  |
Distribution 3 - FY 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Declaration Date |  |  | Oct. 02, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.4225 |  |
Total distributions paid to all classes of unitholders |  |  | $ 15,000 |  |
Distributions per unit declared - distribution date |  |  | Oct. 19, 2017 |  |
Distributions per unit declared - record date |  |  | Oct. 12, 2017 |  |
General Partner |  |  |  |  |
Related Party Transaction |  |  |  |  |
General Partner Distributions |  |  | $ 129 | $ 127 | $ 130
Series A Preferred |  |  |  |  |
Related Party Transaction |  |  |  |  |
Units issued | shares |  | 3,000,000 |  |  | 3,000,000
Preferred Stock Dividend Rate Percentage |  | 9.00% | 9.00% |  |
Preferred stock liquidation preference | $ / shares |  | $ 25 |  |  |
Issuance of preferred units, net of issuance costs incurred |  | $ 72,300 |  |  |
Underwriting discounts and commissions |  | 2,400 |  |  |
Offering costs |  | $ 300 |  |  |
Series A Preferred | Distribution from November 12, 2016 to February 11, 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Declaration Date |  |  | Jan. 19, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.5625 |  |
Distributions per unit declared - distribution date |  |  | Feb. 13, 2017 |  |
Distributions per unit declared - record date |  |  | Feb. 05, 2017 |  |
Series A Preferred | Distribution from February 12, 2017 to May 11, 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Announcement Date |  |  | Apr. 21, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.5625 |  |
Distributions per unit declared - distribution date |  |  | May 12, 2017 |  |
Distributions per unit declared - record date |  |  | May 05, 2017 |  |
Series A Preferred | Distribution from May 12, 2017 to August 11, 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Declaration Date |  |  | Jul. 19, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.5625 |  |
Distributions per unit declared - distribution date |  |  | Aug. 14, 2017 |  |
Distributions per unit declared - record date |  |  | Aug. 05, 2017 |  |
Series A Preferred | Distribution from August 12, 2017 to November 11, 2017 |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution Made To Limited Partner And General Partner Announcement Date |  |  | Oct. 19, 2017 |  |
Distributions paid, Per unit | $ / shares |  |  | $ 0.5625 |  |
Distributions per unit declared - distribution date |  |  | Nov. 13, 2017 |  |
Distributions per unit declared - record date |  |  | Nov. 05, 2017 |  |
Sponsor |  |  |  |  |
Related Party Transaction |  |  |  |  |
Common unitholders - units outstanding | shares |  |  | 15,595,000 |  |
Ownership percentage in Dynagas LNG Partners LP |  |  | 43.90% |  |
Partners' subordinated units converted | shares | 14,985,000 |  |  |  |
Subordinated units converted to Common, Conversion Basis |  |  | one-for-one basis |  |
Subordinated units converted to Common, Conversion Ratio | 1 |  |  |  |
After subordination period |  |  |  |  |
Related Party Transaction |  |  |  |  |
Distribution payment terms |  |  | First, 100% to the holders of common units and to the General Partner in accordance with their relative percentage interests, until the distributed amount in respect of each common unit equals the minimum quarterly distribution; and second, 100% to the holders of common units and to the General Partner in accordance with their relative percentage interests, until each unit has received an aggregate distribution of a specified dollar amount. |  |

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