XML 63 R49.htm IDEA: XBRL DOCUMENT
v3.21.2

Allowance for Credit Losses - Allowance for Credit Loss Activity (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 | Mar. 31, 2021 | Jun. 30, 2020 | Mar. 31, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | $ 115,101 | $ 117,612 | $ 96,850 | $ 62,224 | $ 117,612 | $ 62,224 |
Provision for credit losses on loans | 2,008 |  | 85,831 |  | 5,308 | 104,262 |
Charge-offs | (8,737) |  | (68,303) |  | (15,270) | (79,749) |
Recoveries | 1,264 |  | 231 |  | 1,985 | 520 |
Net (Charge-offs)/Recoveries | (7,473) |  | (68,072) |  | (13,285) | (79,229) |
Balance at End of Period | 109,636 | $ 115,101 | 114,609 | $ 96,850 | 109,636 | 114,609 | $ 62,224
Accounting Standards Update [Extensible List] |  | ASU No. 2016-13 |  | ASU No. 2016-13 |  |  | ASU No. 2016-13
Commercial | Commercial real estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | 66,842 | $ 65,656 | 42,611 | $ 30,577 | 65,656 | 30,577 |
Provision for credit losses on loans | 2,937 |  | 20,681 |  | 4,933 | 28,345 |
Charge-offs | (7,558) |  | (5,600) |  | (8,369) | (6,042) |
Recoveries | 965 |  | 38 |  | 965 | 40 |
Net (Charge-offs)/Recoveries | (6,594) |  | (5,562) |  | (7,403) | (6,002) |
Balance at End of Period | 63,186 | 66,842 | 57,730 | 42,611 | 63,186 | 57,730 | $ 30,577
Commercial | Commercial and industrial |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | 14,663 | 16,100 | 19,870 | 15,681 | 16,100 | 15,681 |
Provision for credit losses on loans | 225 |  | 60,906 |  | 2,953 | 67,104 |
Charge-offs | (473) |  | (61,616) |  | (4,774) | (71,496) |
Recoveries | 11 |  | 4 |  | 148 | 22 |
Net (Charge-offs)/Recoveries | (462) |  | (61,612) |  | (4,627) | (71,474) |
Balance at End of Period | 14,426 | 14,663 | 19,164 | 19,870 | 14,426 | 19,164 | 15,681
Commercial | Commercial construction |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | 6,329 | 7,239 | 6,606 | 7,900 | 7,239 | 7,900 |
Provision for credit losses on loans | (426) |  | 2,249 |  | (1,337) | 4,329 |
Charge-offs | 0 |  | 0 |  | 0 | 0 |
Recoveries | 2 |  | 19 |  | 3 | 21 |
Net (Charge-offs)/Recoveries | 2 |  | 19 |  | 3 | 21 |
Balance at End of Period | 5,905 | 6,329 | 8,874 | 6,606 | 5,905 | 8,874 | 7,900
Commercial | Business banking |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | 15,680 | 15,917 | 13,706 | 0 | 15,917 | 0 |
Provision for credit losses on loans | (560) |  | 918 |  | (46) | 2,126 |
Charge-offs | (410) |  | (260) |  | (1,327) | (721) |
Recoveries | 47 |  | 40 |  | 213 | 101 |
Net (Charge-offs)/Recoveries | (363) |  | (220) |  | (1,115) | (620) |
Balance at End of Period | 14,756 | 15,680 | 14,404 | 13,706 | 14,756 | 14,404 | 0
Consumer | Consumer real estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | 8,981 | 10,014 | 11,200 | 6,337 | 10,014 | 6,337 |
Provision for credit losses on loans | (410) |  | 400 |  | (1,254) | 829 |
Charge-offs | (76) |  | (37) |  | (347) | (218) |
Recoveries | 152 |  | 22 |  | 234 | 112 |
Net (Charge-offs)/Recoveries | 76 |  | (15) |  | (113) | (106) |
Balance at End of Period | 8,647 | 8,981 | 11,585 | 11,200 | 8,647 | 11,585 | 6,337
Consumer | Other consumer |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period | 2,606 | 2,686 | 2,857 | 1,729 | 2,686 | 1,729 |
Provision for credit losses on loans | 243 |  | 677 |  | 61 | 1,529 |
Charge-offs | (221) |  | (790) |  | (453) | (1,272) |
Recoveries | 88 |  | 108 |  | 423 | 224 |
Net (Charge-offs)/Recoveries | (132) |  | (682) |  | (30) | (1,048) |
Balance at End of Period | $ 2,717 | $ 2,606 | 2,852 | 2,857 | $ 2,717 | 2,852 | 1,729
Impact of new accounting standard |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | 0 | 27,352 |  | 27,352 |
Balance at End of Period |  |  |  | 0 |  |  | 27,352
Impact of new accounting standard | Commercial | Commercial real estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | 0 | 4,810 |  | 4,810 |
Balance at End of Period |  |  |  | 0 |  |  | 4,810
Impact of new accounting standard | Commercial | Commercial and industrial |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | 0 | 7,853 |  | 7,853 |
Balance at End of Period |  |  |  | 0 |  |  | 7,853
Impact of new accounting standard | Commercial | Commercial construction |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | 0 | (3,376) |  | (3,376) |
Balance at End of Period |  |  |  | 0 |  |  | (3,376)
Impact of new accounting standard | Commercial | Business banking |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | 0 | 12,898 |  | 12,898 |
Balance at End of Period |  |  |  | 0 |  |  | 12,898
Impact of new accounting standard | Consumer | Consumer real estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | 0 | 4,525 |  | 4,525 |
Balance at End of Period |  |  |  | 0 |  |  | 4,525
Impact of new accounting standard | Consumer | Other consumer |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period |  |  | $ 0 | 642 |  | $ 642 |
Balance at End of Period |  |  |  | $ 0 |  |  | $ 642

X
- Definition Indicates amendment to accounting standards. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL121967933-165497 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL121967933-165497 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 7 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL122642865-165497 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 65 -Paragraph 8 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=123459177&loc=SL121830611-158277 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL121967933-165497 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL121967933-165497 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL120254526-165497 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(iv) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124434974&loc=SL124442142-165695 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(iii) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124434974&loc=SL124442142-165695 Reference 25: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 27: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794 Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437 Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 65 -Paragraph 8 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=123459177&loc=SL121830611-158277 Reference 31: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437 Reference 32: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 33: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(ii) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 34: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=124434974&loc=SL124442142-165695 Reference 35: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 36: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 848 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=122150657&loc=SL122150809-237846 Reference 37: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 38: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL122642865-165497 Reference 39: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S65 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124359872&loc=SL124427846-239511 Reference 40: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 65 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124402435&loc=SL124402458-218513 Reference 41: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 65 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124402435&loc=SL124402458-218513 Reference 42: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 65 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123597120&loc=SL120254526-165497 Reference 43: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 44: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437 Reference 45: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(i) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 46: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124434974&loc=SL124442142-165695 Reference 47: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437 Reference 48: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 49: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 105 -SubTopic 10 -Section 65 -Paragraph 6 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=124434974&loc=SL124442142-165695 Reference 50: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (e)(3) -URI http://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437 Reference 51: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 52: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 53: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 54: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 55: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 10 -Section 65 -Paragraph 4 -Subparagraph (e)(4) -URI http://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437 Reference 56: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 65 -Paragraph 15 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=121322162&loc=SL121327923-165333 Reference 57: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (e)(3) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 58: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 59: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (e)(4) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 60: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 61: http://www.xbrl.org/2003/role/disclosureRef -Topic 848 -SubTopic 10 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Publisher FASB -Subparagraph (a) Reference 62: http://www.xbrl.org/2003/role/disclosureRef -Topic 848 -SubTopic 10 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Publisher FASB -Subparagraph (a)(1) Reference 63: http://www.xbrl.org/2003/role/disclosureRef -Topic 848 -SubTopic 10 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Publisher FASB -Subparagraph (a)(2) Reference 64: http://www.xbrl.org/2003/role/disclosureRef -Topic 848 -SubTopic 10 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Publisher FASB -Subparagraph (a)(3)(iii)(01) Reference 65: http://www.xbrl.org/2003/role/disclosureRef -Topic 848 -SubTopic 10 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Publisher FASB -Subparagraph (a)(3)(iii)(03) + Details
Name: | us-gaap_AccountingStandardsUpdateExtensibleList
Namespace Prefix: | us-gaap_
Data Type: | enum2:enumerationSetItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (4) + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase in allowance for credit loss on financing receivable from recovery. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of credit loss expense (reversal of expense) for financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(11)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_ProvisionForLoanLossesExpensed
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_CommercialAndIndustrialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_BusinessBankingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_ConsumerRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_OtherConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CumulativeEffectPeriodOfAdoptionAxis=srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |