CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY
Distributions paid to unit holders (in dollars per unit)	$ 0.42	$ 0.405	$ 0.10
Cash dividends paid (in dollars per share)	$ 0.42	$ 0.405	$ 0.10

Per unit of ownership amount of cash distributions declared to unit-holder of a limited liability company (LLC).

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=120397183&loc=d3e187085-122770

Name:	us-gaap_DistributionMadeToLimitedLiabilityCompanyLLCMemberDistributionsDeclaredPerUnit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration