Marcus & Millichap, Inc. Quarterly report pursuant to Section 13 or 15(d)

Selected Balance Sheet Data - Schedule of Other Assets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Other Assets [Line Items]
Other assets Current	$ 3,501us-gaap_OtherAssetsCurrent	$ 2,839us-gaap_OtherAssetsCurrent
Other assets Non-Current	4,296us-gaap_OtherAssetsNoncurrent	3,282us-gaap_OtherAssetsNoncurrent
Due from independent contractors [Member]
Other Assets [Line Items]
Other assets Current	1,423	1,577
Other assets Non-Current	2,926	1,820
Security deposits [Member]
Other Assets [Line Items]
Other assets Current	0	0
Other assets Non-Current	1,275	1,240
Customer trust accounts and other [Member]
Other Assets [Line Items]
Other assets Current	2,078	1,262
Other assets Non-Current	$ 95	$ 222