Short answer: The taxable cost goes in boxes 1, 3 and 5 of the W-2 and in box 12 with code C. It is subject to Social Security and Medicare tax, but federal income tax withholding is optional and no FUTA tax is due.
The cost of coverage over $50,000, less what the employee paid, is wages for income tax and for Social Security and Medicare. The employer reports it in boxes 1, 3 and 5 of Form W-2 and also shows it in box 12 with code C.
The employer must collect and pay Social Security and Medicare tax on it, but it does not have to withhold federal income tax (it may, at its option) and does not owe FUTA tax on group term life. Texas has no state income tax, so there is no state withholding question for a Texas employee.
Because the amount is usually small and added every pay period, employees often notice it only as a line on the pay stub. A short explanation at enrollment avoids questions later.