Note Supplemental disclosure on the consolidated statments of cash flows (Additional disclosures on cash flow information cash and due from banks, and restricted cash) (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	[1]	Mar. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Information
Cash and due from banks	$ 355,720			$ 261,864
Restricted cash and due from banks	20,838			18,213
Restricted cash in money market investments	9,185			9,804
Total cash and due from banks, and restricted cash shown in the statement of cash flow	$ 385,743	$ 403,251		$ 289,881	$ 412,629

[1] Refer to Note 5 - Restrictions on cash and due from banks and certain securities for nature of restrictions.