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Loans Receivable, Net Summary of Loans Receivable (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Summary of Loans Receivable |  |
Loans receivable | $ 6,577,824 | $ 5,684,463
Allowance for loan and lease losses | (129,568) | (129,572)
Loans receivable, net | 6,448,256 | 5,554,891
Net deferred origination (fees) costs included in loans receivable | (2,643) | (1,228)
Net purchase accounting (discounts) premiums included in loans receivable | $ (16,325) | $ (12,144)
Weighted-average interest rate on loans (tax-equivalent) | 4.81% | 4.77%
Residential Real Estate | Residential Real Estate |  |
Summary of Loans Receivable |  |
Loans receivable | $ 720,728 | $ 674,347
Allowance for loan and lease losses | (10,798) | (12,436)
Commercial |  |
Summary of Loans Receivable |  |
Loans receivable | 5,156,492 | 4,332,391
Commercial | Commercial Real Estate |  |
Summary of Loans Receivable |  |
Loans receivable | 3,577,139 | 2,990,141
Allowance for loan and lease losses | (68,515) | (65,773)
Commercial | Other Commercial |  |
Summary of Loans Receivable |  |
Loans receivable | 1,579,353 | 1,342,250
Allowance for loan and lease losses | (39,303) | (37,823)
Consumer and Other |  |
Summary of Loans Receivable |  |
Loans receivable | 700,604 | 677,725
Consumer and Other | Home Equity |  |
Summary of Loans Receivable |  |
Loans receivable | 457,918 | 434,774
Allowance for loan and lease losses | (6,204) | (7,572)
Consumer and Other | Other Consumer |  |
Summary of Loans Receivable |  |
Loans receivable | 242,686 | 242,951
Allowance for loan and lease losses | $ (4,748) | $ (5,968)

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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=84173941&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=84173941&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 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 Reference 5: 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=82894903&loc=d3e15032-111544 + Details
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