Consolidated Statements of Comprehensive Income - Unaudited - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income attributable to Bryn Mawr Bank Corporation	$ 14,688	$ 9,433	$ 29,974	$ 18,477
Other comprehensive (loss) income:
Net unrealized (losses) gains arising during the period, net of tax (benefit) expense of $(402), $221, $(1,721), and $430, respectively	(1,512)	411	(6,473)	799
Reclassification adjustment for net gain on sale realized in net income, net of tax expense of $0, $0, $1 and $0, respectively	0	0	(6)	(1)
Reclassification adjustment for net gain realized on transfer of investment securities available for sale to trading, net of tax expense of $0, $0, $88, and $0, respectively	0	0	(329)	0
Unrealized investment (losses) gains, net of tax (benefit) expense of $(402), $221, $(1,810), and $430, respectively	(1,512)	411	(6,808)	798
Net change in unfunded pension liability:
Change in unfunded pension liability related to unrealized loss, prior service cost and transition obligation, net of tax (benefit) expense of $(4), $9, $9, and $25, respectively	(15)	15	31	47
Total other comprehensive (loss) income	(1,527)	426	(6,777)	845
Total comprehensive income	$ 13,161	$ 9,859	$ 23,197	$ 19,322