Navy Columbia (SSBN-826) Class Ballistic Missile Submarine Program: Background and Issues for Congress [December 8, 2017] [open pdf - 1MB]
"The Columbia (SSBN-826) class program, previously known as the Ohio replacement program (ORP) or SSBN(X) program, is a program to design and build a new class of 12 ballistic missile submarines (SSBNs) to replace the Navy's current force of 14 Ohio-class SSBNs. The Navy has identified the Columbia-class program as the Navy's top priority program. The Navy wants to procure the first Columbia-class boat in FY2021. The Navy's proposed FY2018 budget requests $842.9 million in advance procurement (AP) funding and $1,041.7 million in research and development funding for the program."
CRS Report for Congress, R41129
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html