Loans Receivable (Recorded Investment in loans individually evaluated for impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Allowance for loan and lease losses	$ 119,012	$ 234,131
Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	145,213	350,252
Recorded Investment	128,712	325,267
Allowance for loan and lease losses	$ 14,297	$ 65,180
Coverage	11.00%	20.00%
Acquired BBVAPR Accounted for under ASC 310-20 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 251	$ 486
Recorded Investment	230	474
Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	937,864	1,137,377
Recorded Investment	895,577	1,017,976
Allowance for loan and lease losses	$ 29,819	$ 25,785
Coverage	3.00%	3.00%
Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 141,105	$ 241,305
Recorded Investment	125,270	236,964
Allowance for loan and lease losses	$ 22,812	$ 90,178
Coverage	18.00%	38.00%
Commercial impaired loans with specific allowance [Member] \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 16,915	$ 210,718
Recorded Investment	14,949	199,366
Allowance for loan and lease losses	$ 5,572	$ 55,947
Coverage	38.00%	28.00%
Residential troubled-debt restructuring impaired loans with specific allowance [Member] \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 100,390	$ 97,424
Recorded Investment	92,343	89,973
Allowance for loan and lease losses	$ 8,725	$ 9,233
Coverage	9.00%	10.00%
Commercial impaired loans with no specific allowance financing receivable \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 27,908	$ 42,110
Recorded Investment	21,420	35,928
Commercial impaired loans with no specific allowance financing receivable \| Acquired BBVAPR Accounted for under ASC 310-20 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	251	486
Recorded Investment	230	474
Mortgage impaired loan pool [Member] \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	608,751	608,294
Recorded Investment	579,770	608,294
Allowance for loan and lease losses	$ 2,664	$ 1,761
Coverage	0.00%	0.00%
Commercial impaired loan pool [Member] \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 168,980	$ 287,311
Recorded Investment	164,061	168,107
Allowance for loan and lease losses	$ 17,878	$ 15,455
Coverage	11.00%	9.00%
Construction impaired loan pool [Member] \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 52,775	$ 88,180
Recorded Investment	51,271	87,983
Allowance for loan and lease losses	$ 4,120	$ 5,707
Coverage	8.00%	6.00%
Auto impaired loan pool. \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 107,358	$ 153,592
Recorded Investment	100,475	153,592
Allowance for loan and lease losses	$ 5,157	$ 2,862
Coverage	5.00%	2.00%
Consumer impaired loan pool. \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 0	$ 6,713
Recorded Investment	1,488	2,314
Allowance for loan and lease losses	$ 0	$ 243
Coverage	0.00%	11.00%
Loans secured by 1-4 family residential properties, covered [Member] \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 83,216	$ 101,444
Recorded Investment	70,337	92,273
Allowance for loan and lease losses	$ 12,268	$ 22,570
Coverage	17.00%	24.00%
Commercial and Other Construction Loan [Member] \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 57,889	$ 133,148
Recorded Investment	53,445	142,377
Allowance for loan and lease losses	$ 10,544	$ 67,365
Coverage	20.00%	47.00%

The percentage represents the coverage of the allowance for loan and lease losses to loans.

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Amount of investment in impaired financing receivables for which there is 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=49124121&loc=SL6953550-111524

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- Definition

Unpaid principal balance of impaired financing receivables for which there is 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 (a)(4)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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