Equity - Shares related to performance based restricted stock units (Details) - shares	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Performance-Based Restricted Stock Awards (PSAs)
Class Of Stock [Line Items]
Antidilutive securities excluded from computation of EPS	452,007	836,221
Performance Based Restricted Stock Units [Member]
Class Of Stock [Line Items]
Antidilutive securities excluded from computation of EPS	799,166	376,166

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration