LOAN PORTFOLIO - Impaired loans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	$ 238,812	$ 341,485
Unpaid Principal Balance with no Related Allowance	281,868	392,392
Average Recorded Investment No Related Allowance	246,473	352,949
Interest Income with no Related Allowance Accrual Basis	2,244	11,237
Interest Income with No Related Allowance Cash Basis	3,970	1,273
Recorded Investment with Related Allowance	706,595	577,627
Unpaid Principal Balance with Related Allowance	803,716	641,834
Related Allowance	55,205	102,601	221,749
Average Recorded Investment With Related Allowance	724,143	592,928
Interest Income with Related Allowance Accrual Basis	25,909	15,156
Interest Income with Realted Allowance Cash Basis	3,635	2,174
Recorded Investment	945,407	919,112	1,465,294
Unpaid Principal Balance	1,085,584	1,034,226
Average Recorded Investments	970,616	945,877
Interest Income on Impaired Loans Accrual Basis	28,153	26,393
Interest Income on Impaired Loans Cash Basis	7,605	3,447
Fhava Guaranteed Loans [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	0	0
Unpaid Principal Balance with no Related Allowance	0	0
Average Recorded Investment No Related Allowance	0	0
Interest Income with no Related Allowance Accrual Basis	0	0
Interest Income with No Related Allowance Cash Basis	0	0
Recorded Investment with Related Allowance	0	0
Unpaid Principal Balance with Related Allowance	0	0
Related Allowance	0	0
Average Recorded Investment With Related Allowance	0	0
Interest Income with Related Allowance Accrual Basis	0	0
Interest Income with Realted Allowance Cash Basis	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Average Recorded Investments	0	0
Interest Income on Impaired Loans Accrual Basis	0	0
Interest Income on Impaired Loans Cash Basis	0	0
Other Residential Mortgage Loans [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	74,177	220,428
Unpaid Principal Balance with no Related Allowance	80,522	237,709
Average Recorded Investment No Related Allowance	75,711	222,617
Interest Income with no Related Allowance Accrual Basis	1,118	9,513
Interest Income with No Related Allowance Cash Basis	461	1,041
Recorded Investment with Related Allowance	350,067	190,566
Unpaid Principal Balance with Related Allowance	396,203	212,028
Related Allowance	10,854	18,125
Average Recorded Investment With Related Allowance	357,129	193,372
Interest Income with Related Allowance Accrual Basis	15,852	5,623
Interest Income with Realted Allowance Cash Basis	1,853	647
Recorded Investment	424,244	410,994
Unpaid Principal Balance	476,725	449,737
Average Recorded Investments	432,840	415,989
Interest Income on Impaired Loans Accrual Basis	16,970	15,136
Interest Income on Impaired Loans Cash Basis	2,314	1,688
Commercial Mortgage Loans [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	109,271	69,484
Unpaid Principal Balance with no Related Allowance	132,170	73,723
Average Recorded Investment No Related Allowance	113,674	71,367
Interest Income with no Related Allowance Accrual Basis	846	1,494
Interest Income with No Related Allowance Cash Basis	2,670	148
Recorded Investment with Related Allowance	101,467	149,888
Unpaid Principal Balance with Related Allowance	116,329	163,656
Related Allowance	14,289	32,189
Average Recorded Investment With Related Allowance	104,191	153,992
Interest Income with Related Allowance Accrual Basis	1,891	2,114
Interest Income with Realted Allowance Cash Basis	638	1,293
Recorded Investment	210,738	219,372
Unpaid Principal Balance	248,499	237,379
Average Recorded Investments	217,865	225,359
Interest Income on Impaired Loans Accrual Basis	2,737	3,608
Interest Income on Impaired Loans Cash Basis	3,308	1,441
Commercial And Industrial Loan [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	41,131	32,418
Unpaid Principal Balance with no Related Allowance	47,647	56,831
Average Recorded Investment No Related Allowance	42,011	37,946
Interest Income with no Related Allowance Accrual Basis	0	31
Interest Income with No Related Allowance Cash Basis	751	52
Recorded Investment with Related Allowance	195,240	154,686
Unpaid Principal Balance with Related Allowance	226,431	170,191
Related Allowance	21,314	26,686
Average Recorded Investment With Related Allowance	198,930	162,786
Interest Income with Related Allowance Accrual Basis	5,097	4,005
Interest Income with Realted Allowance Cash Basis	564	139
Recorded Investment	236,371	187,104
Unpaid Principal Balance	274,078	227,022
Average Recorded Investments	240,941	200,732
Interest Income on Impaired Loans Accrual Basis	5,097	4,036
Interest Income on Impaired Loans Cash Basis	1,315	191
Construction Loans [Member]
Financing Receivable Impaired [Line Items]
Related Allowance	2,577	22,144
Recorded Investment		72,717
Consumer Auto Loans [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	0	0
Unpaid Principal Balance with no Related Allowance	0	0
Average Recorded Investment No Related Allowance	0	0
Interest Income with no Related Allowance Accrual Basis	0	0
Interest Income with No Related Allowance Cash Basis	0	0
Recorded Investment with Related Allowance	16,991	14,121
Unpaid Principal Balance with Related Allowance	16,991	14,122
Related Allowance	2,787	1,829
Average Recorded Investment With Related Allowance	18,504	12,937
Interest Income with Related Allowance Accrual Basis	1,173	1,017
Interest Income with Realted Allowance Cash Basis	0	0
Recorded Investment	16,991	14,121
Unpaid Principal Balance	16,991	14,122
Average Recorded Investments	18,504	12,937
Interest Income on Impaired Loans Accrual Basis	1,173	1,017
Interest Income on Impaired Loans Cash Basis	0	0
Finance Leases [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	0	0
Unpaid Principal Balance with no Related Allowance	0	0
Average Recorded Investment No Related Allowance	0	0
Interest Income with no Related Allowance Accrual Basis	0	0
Interest Income with No Related Allowance Cash Basis	0	0
Recorded Investment with Related Allowance	2,181	2,359
Unpaid Principal Balance with Related Allowance	2,181	2,359
Related Allowance	253	73
Average Recorded Investment With Related Allowance	2,367	2,219
Interest Income with Related Allowance Accrual Basis	198	281
Interest Income with Realted Allowance Cash Basis	0	0
Recorded Investment	2,181	2,359
Unpaid Principal Balance	2,181	2,359
Average Recorded Investments	2,367	2,219
Interest Income on Impaired Loans Accrual Basis	198	281
Interest Income on Impaired Loans Cash Basis	0	0
Other Consumer Loans [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	3,778	4,035
Unpaid Principal Balance with no Related Allowance	5,072	4,450
Average Recorded Investment No Related Allowance	3,924	3,325
Interest Income with no Related Allowance Accrual Basis	75	139
Interest Income with No Related Allowance Cash Basis	79	30
Recorded Investment with Related Allowance	11,637	8,410
Unpaid Principal Balance with Related Allowance	12,136	8,919
Related Allowance	3,131	1,555
Average Recorded Investment With Related Allowance	12,291	8,919
Interest Income with Related Allowance Accrual Basis	1,634	1,239
Interest Income with Realted Allowance Cash Basis	40	1
Recorded Investment	15,415	12,445
Unpaid Principal Balance	17,208	13,369
Average Recorded Investments	16,215	12,244
Interest Income on Impaired Loans Accrual Basis	1,709	1,378
Interest Income on Impaired Loans Cash Basis	119	31
Land Construction [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	2,994	359
Unpaid Principal Balance with no Related Allowance	6,357	366
Average Recorded Investment No Related Allowance	3,030	360
Interest Income with no Related Allowance Accrual Basis	38	8
Interest Income with No Related Allowance Cash Basis	1	2
Recorded Investment with Related Allowance	9,120	27,711
Unpaid Principal Balance with Related Allowance	12,821	40,348
Related Allowance	794	10,455
Average Recorded Investment With Related Allowance	10,734	28,906
Interest Income with Related Allowance Accrual Basis	64	350
Interest Income with Realted Allowance Cash Basis	25	44
Recorded Investment	12,114	28,070
Unpaid Principal Balance	19,178	40,714
Average Recorded Investments	13,764	29,266
Interest Income on Impaired Loans Accrual Basis	102	358
Interest Income on Impaired Loans Cash Basis	26	46
Residential Construction [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	7,461	14,761
Unpaid Principal Balance with no Related Allowance	10,100	19,313
Average Recorded Investment No Related Allowance	8,123	17,334
Interest Income with no Related Allowance Accrual Basis	167	52
Interest Income with No Related Allowance Cash Basis	8	0
Recorded Investment with Related Allowance	8,102	13,864
Unpaid Principal Balance with Related Allowance	8,834	13,973
Related Allowance	993	2,816
Average Recorded Investment With Related Allowance	8,130	13,640
Interest Income with Related Allowance Accrual Basis	0	0
Interest Income with Realted Allowance Cash Basis	0	50
Recorded Investment	15,563	28,625
Unpaid Principal Balance	18,934	33,286
Average Recorded Investments	16,253	30,974
Interest Income on Impaired Loans Accrual Basis	167	52
Interest Income on Impaired Loans Cash Basis	8	50
Commercial Construction [Member]
Financing Receivable Impaired [Line Items]
Recorded Investment with no Related Allowance	0	0
Unpaid Principal Balance with no Related Allowance	0	0
Average Recorded Investment No Related Allowance	0	0
Interest Income with no Related Allowance Accrual Basis	0	0
Interest Income with No Related Allowance Cash Basis	0	0
Recorded Investment with Related Allowance	11,790	16,022
Unpaid Principal Balance with Related Allowance	11,790	16,238
Related Allowance	790	8,873
Average Recorded Investment With Related Allowance	11,867	16,157
Interest Income with Related Allowance Accrual Basis	0	527
Interest Income with Realted Allowance Cash Basis	515	0
Recorded Investment	11,790	16,022
Unpaid Principal Balance	11,790	16,238
Average Recorded Investments	11,867	16,157
Interest Income on Impaired Loans Accrual Basis	0	527
Interest Income on Impaired Loans Cash Basis	$ 515	$ 0

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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