Note Borrowings (Borrowings by contractual maturities) (Detail) $ in Thousands	Jun. 30, 2018 USD ($)
Debt Disclosure [Line Items]
2018	$ 441,708
2019	655,793
2020	112,035
2021	21,877
2022	105,175
Later years	533,186
Borrowed Funds	1,869,774
Assets Sold Under Agreements To Repurchase
Debt Disclosure [Line Items]
2018	300,911
2019	6,000
2020	0
2021	0
2022	0
Later years	0
Borrowed Funds	306,911
Other Short Term Borrowings
Debt Disclosure [Line Items]
2018	1,200
2019	0
2020	0
2021	0
2022	0
Later years	0
Borrowed Funds	1,200
Notes Payable
Debt Disclosure [Line Items]
2018	139,597
2019	649,793
2020	112,035
2021	21,877
2022	105,175
Later years	533,186
Borrowed Funds	$ 1,561,663