| dk-20200513.xsd | EX-101.SCH - XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT |
| dk-20200513_cal.xml | EX-101.CAL - XBRL TAXONOMY EXTENSION CALCULATION LINKBASE DOCUMENT |
| dk-20200513_def.xml | EX-101.DEF - XBRL TAXONOMY EXTENSION DEFINITION LINKBASE DOCUMENT |
| dk-20200513_lab.xml | EX-101.LAB - XBRL TAXONOMY EXTENSION LABEL LINKBASE DOCUMENT |
| dk-20200513_pre.xml | EX-101.PRE - XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT |
| MetaLinks.json | JSON - IDEA: XBRL DOCUMENT |