Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
Jan. 11, 2019	Dec. 31, 2018
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Total Distribution	$ 13,612
Subsequent Event [Member] \| Long-term Incentive Plan Units One [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.1625000
Dividends, Total Distribution	$ 262
Common Class A [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date		Oct. 13, 2017
Dividends, Record Date		Dec. 22, 2017
Dividends, Date paid		Jan. 05, 2018
Declaration of Dividends, Amount		$ 0.096667
Common Class A [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.1625000
Dividends, Total Distribution	$ 3,819
Common Class C [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date		Oct. 13, 2017
Dividends, Record Date		Dec. 22, 2017
Dividends, Date paid		Jan. 05, 2018
Declaration of Dividends, Amount		$ 0.096667
Common Class C [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.1625000
Dividends, Total Distribution	$ 12
Series A Preferred Stock [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date		Dec. 08, 2017
Dividends, Record Date		Dec. 22, 2017
Dividends, Date paid		Jan. 05, 2018
Declaration of Dividends, Amount		$ 0.515625
Series A Preferred Stock [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.5156250
Dividends, Total Distribution	$ 2,950
Series B Preferred Stock [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date		Oct. 13, 2017
Dividends, Record Date		Dec. 22, 2017
Dividends, Date paid		Jan. 05, 2018
Declaration of Dividends, Amount		$ 5.00
Series B Preferred Stock [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Oct. 12, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 5.0000000
Dividends, Total Distribution	$ 1,530
Series C Preferred Stock [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date		Dec. 08, 2017
Dividends, Record Date		Dec. 22, 2017
Dividends, Date paid		Jan. 05, 2018
Declaration of Dividends, Amount		$ 0.4765625
Series C Preferred Stock [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.4765625
Dividends, Total Distribution	$ 1,107
Series D Preferred Stock [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date		Dec. 08, 2017
Dividends, Record Date		Dec. 22, 2017
Dividends, Date paid		Jan. 05, 2018
Declaration of Dividends, Amount		$ 0.4453125
Series D Preferred Stock [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.4453125
Dividends, Total Distribution	$ 1,269
Operating Partnership Units One [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Dec. 07, 2018
Dividends, Record Date	Dec. 24, 2018
Dividends, Date paid	Jan. 04, 2019
Declaration of Dividends, Amount	$ 0.1625000
Dividends, Total Distribution	$ 1,038
Series B Preferred Stock One [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, Declaration Date	Jan. 11, 2019
Dividends, Record Date	Jan. 25, 2019
Dividends, Date paid	Feb. 05, 2019
Declaration of Dividends, Amount	$ 5.0000000
Dividends, Total Distribution	$ 1,625

Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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