| Document and Entity Information | Dec. 19, 2024 |
| Entity Listings [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Dec. 19, 2024 |
| Entity File Number | 001-36228 |
| Entity Registrant Name | Navient Corporation |
| Entity Central Index Key | 0001593538 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 46-4054283 |
| Entity Address, Address Line One | 13865 Sunrise Valley Drive |
| Entity Address, City or Town | Herndon |
| Entity Address, State or Province | VA |
| Entity Address, Postal Zip Code | 20171 |
| City Area Code | 703 |
| Local Phone Number | 810-3000 |
| Entity Emerging Growth Company | false |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Common Stock [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Common stock, par value $.01 per share |
| Trading Symbol | NAVI |
| Security Exchange Name | NASDAQ |
| 6% Senior Notes due December 15, 2043 [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | 6% Senior Notes due December 15, 2043 |
| Trading Symbol | JSM |
| Security Exchange Name | NASDAQ |
| Preferred Stock Purchase Rights [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Preferred Stock Purchase Rights |
| Trading Symbol | None |
| Security Exchange Name | NASDAQ |
