Allowance for loan losses - Quantitative information by loan class for loans modified as T D R (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) loans	Jun. 30, 2018 USD ($) loans	Jun. 30, 2019 USD ($) loans	Jun. 30, 2018 USD ($) loans
Troubled Debt Restructuring
Loan count \| loans	645	1,025	1,223	1,617
Pre-Modification Recorded Investment	$ 34,890	$ 83,321	$ 67,320	$ 143,987
Post Modification Recorded Investment	32,889	81,356	63,583	139,797
Increase (decrease) in the allowance for loan losses as a result of modification	$ 3,299	$ 17,800	$ 5,358	$ 27,339
Commercial multi-family
Troubled Debt Restructuring
Loan count \| loans	1	1	1	1
Pre-Modification Recorded Investment	$ 154	$ 567	$ 154	$ 567
Post Modification Recorded Investment	116	567	116	567
Increase (decrease) in the allowance for loan losses as a result of modification	$ (5)	$ 43	$ (5)	$ 43
CRE non-owner occupied
Troubled Debt Restructuring
Loan count \| loans	2	6	3	13
Pre-Modification Recorded Investment	$ 2,253	$ 4,460	$ 2,567	$ 27,446
Post Modification Recorded Investment	2,246	4,464	2,557	27,387
Increase (decrease) in the allowance for loan losses as a result of modification	$ 789	$ (46)	$ 807	$ 6,754
CRE owner occupied
Troubled Debt Restructuring
Loan count \| loans	6	26	16	45
Pre-Modification Recorded Investment	$ 1,393	$ 15,096	$ 3,412	$ 20,070
Post Modification Recorded Investment	1,178	14,639	3,151	18,908
Increase (decrease) in the allowance for loan losses as a result of modification	$ 38	$ 845	$ 57	$ 983
Commercial and industrial
Troubled Debt Restructuring
Loan count \| loans	18	32	34	54
Pre-Modification Recorded Investment	$ 4,370	$ 36,153	$ 8,313	$ 47,222
Post Modification Recorded Investment	4,356	35,971	8,835	46,494
Increase (decrease) in the allowance for loan losses as a result of modification	$ 471	$ 13,934	$ 785	$ 13,824
Construction
Troubled Debt Restructuring
Loan count \| loans				1
Pre-Modification Recorded Investment				$ 4,210
Post Modification Recorded Investment				4,293
Increase (decrease) in the allowance for loan losses as a result of modification				$ 474
Mortgages
Troubled Debt Restructuring
Loan count \| loans	185	121	375	203
Pre-Modification Recorded Investment	$ 20,218	$ 15,325	$ 40,950	$ 25,598
Post Modification Recorded Investment	18,320	14,016	36,911	22,935
Increase (decrease) in the allowance for loan losses as a result of modification	$ 687	$ 777	$ 1,358	$ 1,234
Leasing
Troubled Debt Restructuring
Loan count \| loans	1	1	1	1
Pre-Modification Recorded Investment	$ 27	$ 23	$ 27	$ 23
Post Modification Recorded Investment	28	23	28	23
Increase (decrease) in the allowance for loan losses as a result of modification	$ 7	$ 7	$ 7	$ 7
Credit cards
Troubled Debt Restructuring
Loan count \| loans	215	343	404	624
Pre-Modification Recorded Investment	$ 1,772	$ 3,478	$ 3,315	$ 6,404
Post Modification Recorded Investment	1,938	3,503	3,468	6,804
Increase (decrease) in the allowance for loan losses as a result of modification	$ 186	$ 398	$ 357	$ 852
Home equity lines of credit
Troubled Debt Restructuring
Loan count \| loans	11	10	21	19
Pre-Modification Recorded Investment	$ 1,389	$ 860	$ 2,083	$ 1,725
Post Modification Recorded Investment	1,389	817	2,010	1,673
Increase (decrease) in the allowance for loan losses as a result of modification	$ 265	$ 107	$ 320	$ 374
Personal Loan
Troubled Debt Restructuring
Loan count \| loans	194	469	348	631
Pre-Modification Recorded Investment	$ 3,143	$ 7,253	$ 6,290	$ 10,325
Post Modification Recorded Investment	3,142	7,251	6,295	10,321
Increase (decrease) in the allowance for loan losses as a result of modification	$ 830	$ 1,720	$ 1,635	$ 2,730
Auto Loan
Troubled Debt Restructuring
Loan count \| loans	3	3	5	4
Pre-Modification Recorded Investment	$ 38	$ 60	$ 63	$ 194
Post Modification Recorded Investment	43	59	66	191
Increase (decrease) in the allowance for loan losses as a result of modification	$ 8	$ 10	$ 12	$ 33
Other
Troubled Debt Restructuring
Loan count \| loans	9	13	15	21
Pre-Modification Recorded Investment	$ 133	$ 46	$ 146	$ 203
Post Modification Recorded Investment	133	46	146	201
Increase (decrease) in the allowance for loan losses as a result of modification	$ 23	$ 5	$ 25	$ 31

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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