diff --git a/docs/conf.py b/docs/conf.py
index 0666c09..5e81c13 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -30,6 +30,7 @@ MOCK_MODULES = [
     "i3pystatus.pulseaudio.pulse",
     "notmuch",
     "requests",
+    "requests.exceptions",
     "bs4",
     "dota2py",
     "novaclient",
@@ -38,6 +39,7 @@ MOCK_MODULES = [
     "vk",
     "google-api-python-client",
     "dateutil",
+    "dateutil.rrule",
     "httplib2",
     "oauth2client",
     "apiclient",
@@ -48,7 +50,10 @@ MOCK_MODULES = [
     "dateutil.parser",
     "dateutil.relativedelta",
     "xkbgroup",
-    "sensors"
+    "sensors",
+    "khal",
+    "khal.cli",
+    "khal.settings",
 ]
 
 for mod_name in MOCK_MODULES:
diff --git a/docs/i3pystatus.rst b/docs/i3pystatus.rst
index 183de54..26b639e 100644
--- a/docs/i3pystatus.rst
+++ b/docs/i3pystatus.rst
@@ -70,3 +70,39 @@ Weather Backends
 .. autogen:: i3pystatus.weather SettingsBase
 
     .. nothin'
+
+.. calendarbackends:
+
+Calendar Backends
+-----------------
+
+Generic calendar interface. Requires the PyPI package ``colour``.
+
+.. rubric:: Available formatters
+
+* {title} - the title or summary of the event
+* {remaining_time} - how long until this event is due
+
+Additional formatters may be provided by the backend, consult their documentation for details.
+
+.. rubric:: Settings
+
+* {update_interval} - how often (in seconds) the calendar backend should be called to update events
+* {dynamic_color} - when set, the color shifts as the event approaches
+* {urgent_blink} - when set, urgent is toggled every second when within urgent_seconds of the event
+* {urgent_seconds} - how many seconds before the event to begin blinking
+* {skip_recurring} - when set, recurring events are skipped
+
+Here is an example of configuring the calendar module to use the ``Lightning`` backend:
+
+.. code:: python
+
+    status.register("calendar",
+                format="{title} {remaining}",
+                update_interval=10,
+                urgent_blink=True,
+                backend=Lightning(database_path=path, days=2))
+
+.. autogen:: i3pystatus.calendar SettingsBase
+
+    .. nothin'
\ No newline at end of file
diff --git a/i3pystatus/calendar/khal_calendar.py b/i3pystatus/calendar/khal_calendar.py
index 774d5ab..5396271 100644
--- a/i3pystatus/calendar/khal_calendar.py
+++ b/i3pystatus/calendar/khal_calendar.py
@@ -34,8 +34,6 @@ class Khal(CalendarBackend):
         ('days', 'Check for the next X days'),
     )
 
-    required = ('config_path', 'calendars')
-
     days = 7
 
     config_path = None