Document and Entity Information Document
Jan. 21, 2022
Entity Information [Line Items]  
Entity Central Index Key 0001423689
Entity Emerging Growth Company false
Pre-commencement Issuer Tender Offer false
Pre-commencement Tender Offer false
Soliciting Material false
Written Communications false
City Area Code 301
Local Phone Number 968-9300
Entity Incorporation, State or Country Code DE
Entity File Number 001-34057
Document Type 8-K
Document Period End Date Jan. 21, 2022
Entity Registrant Name AGNC INVESTMENT CORP.
Entity Tax Identification Number 26-1701984
Entity Address, Address Line One 2 Bethesda Metro Center, 12th Floor
Entity Address, City or Town Bethesda
Entity Address, State or Province MD
Entity Address, Postal Zip Code 20814
Amendment Flag false
Common Stock [Member]  
Entity Information [Line Items]  
Title of 12(b) Security Common Stock, par value $0.01 per share
Trading Symbol AGNC
Security Exchange Name NASDAQ
Depository shares each representing a 1/1,000th interest in a share of 7.000% Series C Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock [Member]  
Entity Information [Line Items]  
Title of 12(b) Security Depositary shares of 7.000% Series C Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock
Trading Symbol AGNCN
Security Exchange Name NASDAQ
Depository shares each representing a 1/1,000th interest in a share of 6.875% Series D Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock [Member]  
Entity Information [Line Items]  
Title of 12(b) Security Depositary shares of 6.875% Series D Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock
Trading Symbol AGNCM
Security Exchange Name NASDAQ
Depository shares each representing a 1/1000th interest in a share of 6.500% Series E Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock [Member]  
Entity Information [Line Items]  
Title of 12(b) Security Depositary shares of 6.50% Series E Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock
Trading Symbol AGNCO
Security Exchange Name NASDAQ
Depositary shares each representing a 1/1000th interest in a share of 6.125% Series F Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock [Member]  
Entity Information [Line Items]  
Title of 12(b) Security Depositary shares of 6.125% Series F Fixed-to-Floating Rate Cumulative Redeemable Preferred Stock
Trading Symbol AGNCP
Security Exchange Name NASDAQ