How to get the list of items when using groupBy

I'm trying to use groupBy the payroll data using client field. It's working fine but my problem is that I also want to include all the items related to the grouped items. How can I do that? Please see my code below

PayrollController

Payroll::with('employees')
	->select('*')
	->groupBy('client')
	->get();

I tried to use the employees relationship but it only includes 1 employee data.

Payroll Model

public function employees()
{
	return $this->hasMany(Employee::class);
}

Expected output

[
	{
		client: 1,
		total: 1,821
		employee_ids: [1, 2, 3, 4, 29, 50, 89]
	},
	{
		client: 2,
		total: 3,098
		employee_ids: [5, 8, 15, 43]
	}
]