Loans Receivable (Recorded Investment in loans individually evaluated for impairment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Allowance for loan and lease losses	$ 115,937	$ 234,131
Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	162,322	350,252
Recorded Investment	144,789	325,267
Allowance for loan and lease losses	$ 9,387	$ 65,180
Coverage	0.06%	0.11%
Acquired BBVAPR Accounted for under ASC 310-20 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 1,184	$ 486
Recorded Investment	1,150	474
Allowance for loan and lease losses	$ 141	$ 0
Coverage	0.12%	0.00%
Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 887,646	$ 1,137,377
Recorded Investment	850,454	1,017,976
Allowance for loan and lease losses	$ 31,056	$ 25,785
Coverage	0.04%	0.03%
Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 170,038	$ 241,305
Recorded Investment	146,530	236,964
Allowance for loan and lease losses	$ 21,281	$ 90,178
Coverage	0.15%	0.38%
Commercial impaired loans with specific allowance [Member] \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 13,183	$ 210,718
Recorded Investment	11,698	199,366
Allowance for loan and lease losses	$ 1,626	$ 55,947
Coverage	0.14%	0.13%
Commercial impaired loans with specific allowance [Member] \| Acquired BBVAPR Accounted for under ASC 310-20 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 944
Recorded Investment	929
Allowance for loan and lease losses	$ 141
Coverage	0.15%
Residential troubled-debt restructuring impaired loans with specific allowance [Member] \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 100,101	$ 97,424
Recorded Investment	91,650	89,973
Allowance for loan and lease losses	$ 7,761	$ 9,233
Coverage	0.08%	0.09%
Commercial impaired loans with no specific allowance financing receivable \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 49,038	$ 42,110
Recorded Investment	$ 41,441	$ 35,928
Coverage	0.00%	0.00%
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	$ 240	$ 486
Recorded Investment	$ 221	$ 474
Coverage	0.00%	0.00%
Mortgage impaired loan pool [Member] \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 595,757	$ 608,294
Recorded Investment	569,250	608,294
Allowance for loan and lease losses	$ 2,682	$ 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	$ 160,254	$ 287,311
Recorded Investment	156,241	168,107
Allowance for loan and lease losses	$ 19,873	$ 15,455
Coverage	0.13%	0.09%
Construction impaired loan pool [Member] \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 38,838	$ 88,180
Recorded Investment	39,287	87,983
Allowance for loan and lease losses	$ 3,579	$ 5,707
Coverage	0.09%	0.06%
Auto impaired loan pool. \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 92,797	$ 153,592
Recorded Investment	85,676	153,592
Allowance for loan and lease losses	$ 4,922	$ 2,862
Coverage	0.06%	0.02%
Consumer impaired loan pool. \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 29	$ 6,713
Recorded Investment	1,372	2,314
Allowance for loan and lease losses	$ 6	$ 243
Coverage	0.00%	0.11%
Loans secured by 1-4 family residential properties, covered [Member] \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 88,017	$ 101,444
Recorded Investment	73,018	92,273
Allowance for loan and lease losses	$ 11,947	$ 22,570
Coverage	0.16%	0.24%
Commercial and Other Construction Loan [Member] \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 81,992	$ 133,148
Recorded Investment	72,140	142,377
Allowance for loan and lease losses	$ 9,328	$ 67,365
Coverage	0.13%	0.47%

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- Definition

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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