So I have this form with these fields

{{ Form::open(array('url' => 'user', 'id' => 'user_create_form')) }}

    <div class="form-input-element">
        <label for="facebook_id">ID Facebook</label>
        {{ Form::text('facebook_id', Input::old('facebook_id'), array('placeholder' => 'ID Facebook')) }}
    </div>

    <div class="form-input-element">
        <label for="twitter_id">ID Twitter</label>
        {{ Form::text('twitter_id', Input::old('twitter_id'), array('placeholder' => 'ID Twitter')) }}
    </div>

    <div class="form-input-element">
        <label for="instagram_id">ID Instagram</label>
        {{ Form::text('instagram_id', Input::old('instagram_id'), array('placeholder' => 'ID Instagram')) }}
    </div>

{{ Form::close() }}

I'd like to tell Laravel that at least one of these fields is required. How do I do that using the Validator?

$rules = array(
    'facebook_id'                   => 'required',
    'twitter_id'                    => 'required',
    'instagram_id'                  => 'required',
);
$validator = Validator::make(Input::all(), $rules);