GOODWILL AND OTHER INTANGIBLES - Gross Amount and Accumulated Amortization of Other Intangible Assets (Detail) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
Mar. 31, 2018 |
Dec. 31, 2017 |
Jun. 30, 2012 |
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Goodwill And Intangible Assets Disclosure [Abstract] | ||||||||||
Finite Lived Intangible Assets Amortization Expense Year Two | $ 3,088 | |||||||||
Finite Lived Intangible Assets Amortization Expense Year Three | 2,851 | |||||||||
Finite Lived Intangible Assets Amortization Expense Year Four | 2,658 | |||||||||
Finite Lived Intangible Assets Amortization Expense After Year Five | 1,150 | |||||||||
Finite Lived Intangible Assets Amortization Expense Remainder Of Fiscal Year | 2,585 | |||||||||
Finite Lived Intangible Assets Amortization Expense Year Five | 915 | |||||||||
Core Deposits [Member] | ||||||||||
Finite Lived Intangible Assets [Line Items] | ||||||||||
Gross amount | 51,664 | $ 51,664 | ||||||||
Accumulated amortization | [1] | (46,580) | (46,186) | |||||||
Net carrying amount | $ 5,084 | $ 5,478 | ||||||||
Remaining amortization period | 6 years 9 months 18 days | 7 years | ||||||||
Purchased Credit Card Relationship Intangible [Member] | ||||||||||
Finite Lived Intangible Assets [Line Items] | ||||||||||
Gross amount | $ 24,465 | $ 24,465 | $ 24,500 | |||||||
Accumulated amortization | [2] | (17,039) | (16,465) | |||||||
Net carrying amount | $ 7,426 | $ 8,000 | ||||||||
Remaining amortization period | 3 years 7 months 6 days | 3 years 10 months 24 days | ||||||||
Customer Related Intangible Assets [Member] | ||||||||||
Finite Lived Intangible Assets [Line Items] | ||||||||||
Gross amount | $ 1,067 | $ 1,067 | ||||||||
Accumulated amortization | [3] | (330) | (292) | |||||||
Net carrying amount | $ 737 | $ 775 | ||||||||
Remaining amortization period | 4 years 8 months 12 days | 5 years | ||||||||
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