Note Deposits (Total interest bearing deposits) (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Deposits Abstract
Savings accounts	$ 8,040,047	$ 7,793,533
NOW, money market abd other interest bearing demand deposits	9,197,237	8,012,706
Total savings, NOW, money market and other interest bearing demand deposits	17,237,284	15,806,239
Time Deposits Abstract
Under $100,000	3,552,834	3,570,956
$100,000 and over	4,160,133	4,138,586
Total certificates of deposit	7,712,967	7,709,542
Total interest bearing deposits	$ 24,950,251	$ 23,515,781