Loans receivable (Details 10) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Loan payment delinquencies
30-59 days delinquent	$ 40,674	$ 45,985
60-89 days delinquent	8,803	13,324
90 days or greater delinquent	32,913	41,326
Total delinquency	82,390	100,635
Current	5,982,474	5,889,256
Total loans	6,064,864	5,989,891
Personal Banking
Loan payment delinquencies
30-59 days delinquent	33,697	38,767
60-89 days delinquent	6,316	11,077
90 days or greater delinquent	22,759	26,752
Total delinquency	62,772	76,596
Current	3,776,793	3,753,735
Total loans	3,839,565	3,830,331
Personal Banking \| Residential mortgage loans
Loan payment delinquencies
30-59 days delinquent	25,586	27,443
60-89 days delinquent	3,397	6,970
90 days or greater delinquent	15,068	17,696
Total delinquency	44,051	52,109
Current	2,499,819	2,469,347
Total loans	2,543,870	2,521,456
Personal Banking \| Home equity loans
Loan payment delinquencies
30-59 days delinquent	3,737	5,752
60-89 days delinquent	1,404	1,672
90 days or greater delinquent	5,646	6,606
Total delinquency	10,787	14,030
Current	1,044,952	1,052,101
Total loans	1,055,739	1,066,131
Personal Banking \| Other consumer loans
Loan payment delinquencies
30-59 days delinquent	4,374	5,572
60-89 days delinquent	1,515	2,435
90 days or greater delinquent	2,045	2,450
Total delinquency	7,934	10,457
Current	232,022	232,287
Total loans	239,956	242,744
Business Banking
Loan payment delinquencies
30-59 days delinquent	6,977	7,218
60-89 days delinquent	2,487	2,247
90 days or greater delinquent	10,154	14,574
Total delinquency	19,618	24,039
Current	2,205,681	2,135,521
Total loans	2,225,299	2,159,560
Business Banking \| Commercial real estate loans
Loan payment delinquencies
30-59 days delinquent	5,497	4,956
60-89 days delinquent	2,351	2,038
90 days or greater delinquent	8,233	11,099
Total delinquency	16,081	18,093
Current	1,840,493	1,783,091
Total loans	1,856,574	1,801,184
Business Banking \| Commercial loans
Loan payment delinquencies
30-59 days delinquent	1,480	2,262
60-89 days delinquent	136	209
90 days or greater delinquent	1,921	3,475
Total delinquency	3,537	5,946
Current	365,188	352,430
Total loans	$ 368,725	$ 358,376

Financing receivables that are less than 60 days past due but more than 29 days past due.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes 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 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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