| Cover | Dec. 27, 2019 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Dec. 27, 2019 |
| Entity File Number | 001-36677 |
| Entity Registrant Name | Diplomat Pharmacy, Inc. |
| Entity Central Index Key | 0001610092 |
| Entity Tax Identification Number | 38-2063100 |
| Entity Incorporation, State or Country Code | MI |
| Entity Address, Address Line One | 4100 S. Saginaw St. |
| Entity Address, City or Town | Flint |
| Entity Address, State or Province | MI |
| Entity Address, Postal Zip Code | 48507 |
| City Area Code | 888 |
| Local Phone Number | 720-4450 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, no par value per share |
| Trading Symbol | DPLO |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
