Note Other Real Estate Owned (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Other Real Estate Owned Rollforward
Balance at beginning of the period	$ 136,705	$ 188,855
Write-downs in value	(2,181)	(3,455)
Additions	8,934	7,387
Sales	(17,847)	(23,976)
Other adjustments	(133)	(417)
Ending balance	125,478	168,394
Non-covered loans | Mortgages
Other Real Estate Owned Rollforward
Balance at beginning of the period	114,911	147,849
Write-downs in value	(1,610)	(2,514)
Additions	7,764	2,984
Sales	(16,333)	(20,305)
Other adjustments	(133)	(588)
Ending balance	104,599	127,426
Non-covered loans | Commercial / Construction
Other Real Estate Owned Rollforward
Balance at beginning of the period	21,794	21,411
Write-downs in value	(571)	(654)
Additions	1,170	4,403
Sales	(1,514)	(389)
Other adjustments	0	864
Ending balance	$ 20,879	25,635
Covered loans | Mortgages
Other Real Estate Owned Rollforward
Balance at beginning of the period		19,595
Write-downs in value		(287)
Additions		0
Sales		(3,282)
Other adjustments		(693)
Ending balance		$ 15,333