Update Get-CASMailbox.md

Added information about the "-RecipientTypeDetails" filter.
Copied its definition from the Get-Mailbox article.

Author: Luspin

exchange/exchange-ps/exchange/Get-CASMailbox.md

@@ -40,6 +40,7 @@ Get-CASMailbox [-Anr <String>]
  [-SortBy <String>]
  [-ReadIsOptimizedForAccessibility]
  [-RecalculateHasActiveSyncDevicePartnership] [<CommonParameters>]
+ [-RecipientTypeDetails <RecipientTypeDetails[]>]
 ```
 
 ### Identity
@@ -59,6 +60,7 @@ Get-CASMailbox [[-Identity] <MailboxIdParameter>]
  [-SortBy <String>]
  [-ReadIsOptimizedForAccessibility]
  [-RecalculateHasActiveSyncDevicePartnership] [<CommonParameters>]
+ [-RecipientTypeDetails <RecipientTypeDetails[]>]
 ```
 
 ## DESCRIPTION
@@ -99,6 +101,14 @@ Get-CASMailbox [email protected] | Format-List Ews*
 
 This example returns all Exchange Web Services settings for the user [email protected].
 
+
+### Example 4
+```powershell
+Get-CASMailbox -RecipientTypeDetails SharedMailbox | Select *
+```
+
+This example filters the cmdlet output to only include Shared mailboxes.
+
 ## PARAMETERS
 
 ### -ActiveSyncDebugLogging
@@ -409,6 +419,46 @@ Accept pipeline input: False
 Accept wildcard characters: False
 ```
 
+### -RecipientTypeDetails
+The RecipientTypeDetails parameter filters the results by the specified mailbox subtype. Valid values are:
+
+- DiscoveryMailbox
+
+- EquipmentMailbox
+
+- GroupMailbox
+
+- LegacyMailbox
+
+- LinkedMailbox
+
+- LinkedRoomMailbox
+
+- RoomMailbox
+
+- SchedulingMailbox
+
+- SharedMailbox
+
+- TeamMailbox
+
+- UserMailbox
+
+You can specify multiple values separated by commas.
+
+```yaml
+Type: RecipientTypeDetails[]
+Parameter Sets: (All)
+Aliases:
+Applicable: Exchange Server 2010, Exchange Server 2013, Exchange Server 2016, Exchange Server 2019, Exchange Online
+
+Required: False
+Position: Named
+Default value: None
+Accept pipeline input: False
+Accept wildcard characters: False
+```
+
 ### -ResultSize
 The ResultSize parameter specifies the maximum number of results to return. If you want to return all requests that match the query, use unlimited for the value of this parameter. The default value is 1000.