When entering your ROTH IRA values, they are done separately since you have separate accounts of investments.
Also, the value will be on your statement as of December 31, 2017 with the institutional holding your account.
You are not required to report your prior year contributions and value. TurboTax asks if you would like us to keep up with these figures for you. You will need the information when you take a distribution to determine what part of your ROTH is taxable.
The following information from the IRS on ROTH's may be helpful: