Loans (Recorded Investment in loans individually evaluated for impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Allowance for loan and lease losses	$ 162,642	$ 164,231
Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	189,861	188,536
Recorded Investment	166,195	165,403
Allowance for loan and lease losses	$ 19,783	$ 18,620
Coverage	0.12%	0.11%
Acquired BBVAPR Accounted for under ASC 310-20 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 926	$ 926
Recorded Investment	678	747
Allowance for loan and lease losses	$ 27	$ 14
Coverage	0.04%	0.02%
Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 638,656	$ 701,501
Recorded Investment	629,352	688,083
Allowance for loan and lease losses	$ 45,427	$ 42,010
Coverage	7.00%	6.00%
Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 102,285	$ 117,510
Recorded Investment	98,375	111,230
Allowance for loan and lease losses	$ 25,578	$ 24,971
Coverage	0.26%	0.22%
Commercial impaired loans with specific allowance [Member] \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 54,895	$ 54,636
Recorded Investment	50,524	49,092
Allowance for loan and lease losses	$ 9,168	$ 8,434
Coverage	0.18%	0.17%
Commercial impaired loans with specific allowance [Member] \| Acquired BBVAPR Accounted for under ASC 310-20 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 926	$ 926
Recorded Investment	678	747
Allowance for loan and lease losses	$ 27	$ 14
Coverage	0.04%	0.02%
Residential troubled-debt restructuring impaired loans with specific allowance [Member] \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 94,501	$ 95,659
Recorded Investment	83,093	84,174
Allowance for loan and lease losses	$ 10,615	$ 10,186
Coverage	0.13%	0.12%
Commercial impaired loans with no specific allowance financing receivable \| Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 40,465	$ 38,241
Recorded Investment	$ 32,578	$ 32,137
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	$ 0	$ 0
Recorded Investment	$ 0	$ 0
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	$ 479,998	$ 498,537
Recorded Investment	476,080	492,890
Allowance for loan and lease losses	$ 25,208	$ 15,225
Coverage	5.00%	3.00%
Commercial impaired loan pool [Member] \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 151,265	$ 188,413
Recorded Investment	146,810	180,790
Allowance for loan and lease losses	$ 17,083	$ 20,641
Coverage	12.00%	11.00%
Auto impaired loan pool. \| Acquired BBVAPR Accounted under ASC 310-30 [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 7,393	$ 14,551
Recorded Investment	6,462	14,403
Allowance for loan and lease losses	$ 3,136	$ 6,144
Coverage	49.00%	43.00%
Consumer impaired loan pool. \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal		$ 15
Recorded Investment		4
Allowance for loan and lease losses		$ 4
Coverage		1.00%
Loans secured by 1-4 family residential properties, covered [Member] \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 65,870	$ 70,153
Recorded Investment	59,956	63,406
Allowance for loan and lease losses	$ 17,213	$ 15,382
Coverage	0.29%	0.24%
Commercial and Other Construction Loan [Member] \| Eurobank Acquired Loans
Financing Receivable, Impaired [Line Items]
Unpaid Principal	$ 36,415	$ 47,342
Recorded Investment	38,419	47,820
Allowance for loan and lease losses	$ 8,365	$ 9,585
Coverage	0.22%	0.20%

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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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.

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