Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue from Contract with Customer [Abstract]
Trust and investment services	$ 3,262	$ 2,800	$ 6,492	$ 5,544
Insurance commissions	4,026	4,358	7,847	9,419
Service charges on deposit accounts	6,679	5,342	13,932	10,578
(Losses) gains on securities transactions, net	(36)	22	(801)	(1)
Fees from loan servicing	2,045	1,831	4,268	3,646
Gains on sales of loans, net	7,642	4,791	14,395	8,919
Bank owned life insurance	2,652	1,701	4,415	4,164
Other	11,799	7,985	19,772	12,281
Total non-interest income	$ 38,069	$ 28,830	$ 70,320	$ 54,550

Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

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- Definition

Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from nontransaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) use of automated teller machines or remote service units; (9) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (10) issuing stop payment orders; (11) certifying checks; and (12) accumulating or disbursing funds deposited in IRAs or Keogh Plan accounts when not handled by the bank's trust department. This item does not include penalties assessed on the early withdrawal of time deposits.

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- Definition

Income from services rendered by trust departments or by any consolidated subsidiaries acting in a fiduciary capacity, including fees earned for (1) acting as an agent for fiduciary placement and loans and (2) custody or investment advisory services when such fees are not separately billed to the customer. This item excludes commissions and fees received for the accumulation or disbursement of funds deposited to Individual Retirement or Keogh plan accounts when such are not handled by the reporting entity's trust department.

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- Definition

The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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- Definition

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3(a))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products.

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- Definition

The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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- Definition

Amount of revenue earned, classified as other, excluding interest income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-03(1)(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20187-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(4))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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- References

No definition available.

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- Definition

Amount of revenue from servicing real estate mortgages, credit cards, and other financial assets held by others. Includes premiums received in lieu of regular servicing fees.

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