Amerant Bancorp (AMTB) 8-K 18 Dec 19 2019 Q1 Other Events Financial data

Document and Entity Information

Document and Entity Information Statement	Dec. 18, 2019
Document and Entity Information [Abstract]
Document Type	8-K
Entity Registrant Name	Amerant Bancorp Inc.
Document Period End Date	Dec. 18, 2019
Amendment Flag	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2019

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 26,821	$ 25,756	$ 44,531
Interest earning deposits with banks	62,868	59,954	108,914
Cash and cash equivalents	89,689	85,710	153,445
Securities
Available for sale	1,551,591	1,586,051	1,687,157
Held to maturity	83,909	85,188	89,860
Federal Reserve Bank and Federal Home Loan Bank stock	65,828	70,189	69,934
Securities	1,701,328	1,741,428	1,846,951
Loans held for sale	9,968	0	5,611
Loans, gross	5,734,438	5,920,175	6,066,225
Less: Allowance for loan losses	60,322	61,762	72,000
Loans, net	5,674,116	5,858,413	5,994,225
Bank owned life insurance	207,546	206,142	200,318
Premises and equipment, net	123,930	123,503	129,357
Deferred tax assets, net	9,858	16,310	14,583
Goodwill	19,193	19,193	19,193
Accrued interest receivable and other assets	66,727	73,648	73,084
Total assets	7,902,355	8,124,347	8,436,767
Deposits
Noninterest bearing	775,015	768,822	895,710
Interest bearing	1,229,487	1,288,030	1,496,749
Savings and money market	1,524,554	1,588,703	1,684,080
Time	2,359,132	2,387,131	2,246,434
Total deposits	5,888,188	6,032,686	6,322,973
Advances from the Federal Home Loan Bank and other borrowings	1,070,000	1,166,000	1,173,000
Junior subordinated debentures held by trust subsidiaries	118,110	118,110	118,110
Accounts payable, accrued liabilities and other liabilities	47,308	60,133	69,234
Total liabilities	7,123,606	7,376,929	7,683,317
Commitments and contingencies (Note 16)
Stockholders’ equity
Additional paid in capital	415,864	385,367	367,505
Treasury stock, at cost; 1,420,136 Class B common shares		(17,908)	0
Retained earnings	406,733	393,662	387,829
Accumulated other comprehensive loss	(2,149)	(18,164)	(6,133)
Total stockholders' equity	778,749	747,418	753,450
Total liabilities and stockholders' equity	7,902,355	8,124,347	8,436,767
Class A common stock
Stockholders’ equity
Common stock	2,899	2,686	2,474
Class B common stock
Stockholders’ equity
Common stock	1,775	1,775	$ 1,775
Treasury stock, at cost; 1,420,136 Class B common shares	$ (46,373)	$ (17,908)

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2019	Mar. 07, 2019	Dec. 31, 2018	Feb. 06, 2018	Dec. 31, 2017
Common stock, shares authorized (in shares)			500,000,000
Class A
Common stock, par value (in dollars per share)	$ 0.10		$ 0.10		$ 0.10
Common stock, shares authorized (in shares)	400,000,000		400,000,000		400,000,000
Common stock, shares issued (in shares)	28,985,996		26,851,832	74,212,408	24,737,470
Common stock, shares outstanding (in shares)	28,985,996		26,851,832		24,737,470
Class B
Common stock, par value (in dollars per share)	$ 0.10		$ 0.10		$ 0.10
Common stock, shares authorized (in shares)	100,000,000		100,000,000		100,000,000
Common stock, shares issued (in shares)	17,751,053		17,751,053	53,253,157	17,751,053
Common stock, shares outstanding (in shares)	14,218,596		17,751,053		17,751,053
Common stock, shares outstanding (in shares)			16,330,917
Treasury stock (in shares)	3,532,457	2,112,321	1,420,136

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest income
Loans	$ 66,722	$ 59,670	$ 257,611	$ 223,765	$ 188,526
Investment securities	12,581	11,741	49,207	47,913	49,495
Interest earning deposits with banks	1,004	520	2,540	1,642	806
Total interest income	80,307	71,931	309,358	273,320	238,827
Interest expense
Interest bearing demand deposits	274	89	657	394	653
Savings and money market deposits	3,733	2,584	12,911	8,856	8,306
Time deposits	12,553	8,700	42,189	26,787	16,576
Advances from the Federal Home Loan Bank	6,205	5,990	26,470	18,235	10,971
Junior subordinated debentures	2,105	1,935	8,086	7,456	7,129
Securities sold under agreements to repurchase			6	1,882	3,259
Total interest expense	24,870	19,298	90,319	63,610	46,894
Net interest income	55,437	52,633	219,039	209,710	191,933
Provision for (reversal of) loan losses	0	0	375	(3,490)	22,110
Net interest income after provision for loan losses	55,437	52,633	218,664	213,200	169,823
Noninterest income
Deposits and service fees	4,086	4,582	17,753	19,560	20,928
Brokerage, advisory and fiduciary activities	3,688	4,415	16,849	20,626	20,282
Change in cash surrender value of bank owned life insurance	1,404	1,444	5,824	5,458	4,422
Cards and trade finance servicing fees	915	1,062	4,424	4,589	4,250
Data processing, rental income and fees for other services to related parties	520	881	2,517	3,593	4,409
Gain on early extinguishment of advances from the Federal Home Loan Bank	557	0	882	0	714
Securities (losses) gains, net	4	0	(999)	(1,601)	1,031
Other noninterest income	1,982	1,561	6,625	19,260	6,234
Total noninterest income	13,156	13,945	53,875	71,485	62,270
Noninterest expense
Salaries and employee benefits	33,437	34,041	141,801	131,800	129,681
Professional and other services fees	3,444	6,444	19,119	16,399	11,937
Occupancy and equipment	4,042	3,715	16,531	17,381	18,368
Telecommunication and data processing	3,026	3,084	12,399	9,825	8,392
Depreciation and amortization	1,942	2,141	8,543	9,040	9,130
FDIC assessments and insurance	1,393	1,447	6,215	7,624	7,131
Other operating expenses	4,661	4,773	10,365	15,567	13,664
Total noninterest expenses	51,945	55,645	214,973	207,636	198,303
Net income before income tax	16,648	10,933	57,566	77,049	33,790
Income tax expense	(3,577)	(1,504)	(11,733)	(33,992)	(10,211)
Net income	13,071	9,429	45,833	43,057	23,579
Other comprehensive (loss) income, net of tax
Net unrealized holding (losses) gains on securities available for sale arising during the period	16,278	(14,977)	(15,265)	3,577	(3,839)
Net unrealized holding gains (losses) on cash flow hedges arising during the period	(11)	4,280	2,663	152	3,598
Reclassification adjustment for net losses (gains) included in net income	(252)	90	571	833	(1,004)
Other comprehensive (loss) income	16,015	(10,607)	(12,031)	4,562	(1,245)
Comprehensive income	$ 29,086	$ (1,178)	$ 33,802	$ 47,619	$ 22,334
Basic and diluted income per common share (Note 20) (in dollars per share)			$ 1.08	$ 1.01	$ 0.55

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Class A	Class B	Common StockClass A	Common StockClass B	Additional Paid in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Shares Outstanding (in shares) at Dec. 31, 2015				24,737,470	17,751,053
Shares Issued (in shares) at Dec. 31, 2015				24,737,470	17,751,053
Beginning balance at Dec. 31, 2015	$ 682,403			$ 2,474	$ 1,775	$ 367,505	$ 0	$ 320,099	$ (9,450)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	23,579							23,579
Other comprehensive) income (loss	(1,245)								(1,245)
Shares Outstanding (in shares) at Dec. 31, 2016				24,737,470	17,751,053
Shares Issued (in shares) at Dec. 31, 2016				24,737,470	17,751,053
Ending balance at Dec. 31, 2016	704,737			$ 2,474	$ 1,775	367,505	0	343,678	(10,695)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	43,057							43,057
Reclassification of tax law impact on AOCI	0							1,094	(1,094)
Other comprehensive income	5,656								5,656
Other comprehensive) income (loss	4,562
Shares Outstanding (in shares) at Dec. 31, 2017		24,737,470	17,751,053	24,737,470	17,751,053
Shares Issued (in shares) at Dec. 31, 2017		24,737,470	17,751,053	24,737,470	17,751,053
Ending balance at Dec. 31, 2017	753,450			$ 2,474	$ 1,775	367,505	0	387,829	(6,133)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,429							9,429
Dividends	(40,000)							(40,000)
Other comprehensive) income (loss	(10,607)								(10,607)
Shares Outstanding (in shares) at Mar. 31, 2018				24,737,470	17,751,053
Ending balance at Mar. 31, 2018	712,272			$ 2,474	$ 1,775	367,505	0	357,258	(16,740)
Shares Outstanding (in shares) at Dec. 31, 2017		24,737,470	17,751,053	24,737,470	17,751,053
Shares Issued (in shares) at Dec. 31, 2017		24,737,470	17,751,053	24,737,470	17,751,053
Beginning balance at Dec. 31, 2017	753,450			$ 2,474	$ 1,775	367,505	0	387,829	(6,133)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued (in shares)				1,377,523
Common stock issued	17,908			$ 138		17,770
Repurchase of Class B common stock (in shares)					0
Repurchase of Class B common stock	(17,908)						(17,908)
Restricted stock issued (in shares)				736,839
Restricted stock issued	0			$ 74		(74)
Stock-based compensation expense	166					166
Net income	45,833							45,833
Dividends	(40,000)							(40,000)
Other comprehensive) income (loss	(12,031)								(12,031)
Shares Outstanding (in shares) at Dec. 31, 2018		26,851,832	17,751,053	26,851,832	17,751,053
Shares Issued (in shares) at Dec. 31, 2018		26,851,832	17,751,053	26,851,832	17,751,053
Ending balance at Dec. 31, 2018	747,418			$ 2,686	$ 1,775	385,367	(17,908)	393,662	(18,164)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares outstanding (in shares)			16,330,917		16,330,917
Common stock issued (in shares)				2,132,865
Common stock issued	29,218			$ 213		29,005
Repurchase of Class B common stock (in shares)					(2,112,321)
Repurchase of Class B common stock	(28,465)						(28,465)
Restricted stock issued (in shares)				1,299
Restricted stock issued	0
Stock-based compensation expense	1,492					1,492
Net income	13,071							13,071
Other comprehensive) income (loss	16,015								16,015
Shares Outstanding (in shares) at Mar. 31, 2019		28,985,996	14,218,596	28,985,996	14,218,596
Shares Issued (in shares) at Mar. 31, 2019		28,985,996	17,751,053
Ending balance at Mar. 31, 2019	$ 778,749			$ 2,899	$ 1,775	$ 415,864	$ (46,373)	$ 406,733	$ (2,149)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income	$ 13,071	$ 9,429	$ 45,833	$ 43,057	$ 23,579
Adjustments to reconcile net income to net cash provided by operating activities
Provision for (reversal of) loan losses	0	0	375	(3,490)	22,110
Net premium amortization on securities	3,453	4,411	16,926	19,357	27,264
Depreciation and amortization	1,942	2,141	8,543	9,040	9,130
Stock-based compensation expense	1,492	0	166	0	0
Increase in cash surrender value of bank owned life insurance	(1,404)	(1,444)	(5,824)	(5,458)	(4,422)
Net gain on sale of premises and equipment			0	(11,319)	(1,956)
Deferred taxes, securities net gains or losses and others	1,238	(5,349)	2,270	14,684	(3,991)
Gain on early extinguishment of advances from the FHLB	(557)	0	(882)	0	(714)
Net changes in operating assets and liabilities
Loans held for sale			0	(5,705)	(4,730)
Accrued interest receivable and other assets	8,777	(6,679)	3,655	(1,257)	(7,937)
Account payable, accrued liabilities and other liabilities	(15,431)	11,132	(8,901)	14,373	16,935
Net cash provided by operating activities	12,581	13,641	62,161	73,282	75,268
Purchases of investment securities:
Available for sale	(110,170)	(60,793)	(216,237)	(231,675)	(1,084,029)
Held to maturity securities			0	(90,196)	0
Federal Home Loan Bank stock	(4,888)	(6,802)	(27,667)	(41,044)	(53,350)
Purchases of investment securities	(115,058)	(67,595)	(243,904)	(362,915)	(1,137,379)
Maturities, sales and calls of investment securities:
Available for sale	162,796	57,028	279,959	655,305	986,041
Held to maturity	1,205	531	4,400	315	0
Federal Home Loan Bank stock	9,248	4,250	27,413	30,600	44,253
Maturities, sales and calls of investment securities	173,249	61,809	311,772	686,220	1,030,294
Net increase in loans	22,173	108,571	(33,199)	(393,636)	(259,931)
Proceeds from loan portfolio sales	152,177	12,958	173,473	85,767	105,164
Purchase of bank owned life insurance			0	(30,000)	(60,000)
Purchases of premises and equipment	(1,951)	(1,904)	(10,044)	(8,606)	(8,535)
Proceeds from sales of premises and equipment and others			911	30,737	8,159
Net proceeds from sale of subsidiary	0	7,500	7,500	0	0
Net cash provided by (used in) investing activities	230,590	121,339	206,509	7,567	(322,228)
Cash flows from financing activities
Net decrease in demand, savings and money market accounts	(116,499)	(96,787)	(430,984)	(663,568)	(388,520)
Net increase in time deposits	(27,999)	54,019	140,697	409,175	446,211
Net decrease in securities sold under agreements to repurchase			0	(50,000)	(23,488)
Proceeds from Advances from the Federal Home Loan Bank and other borrowings	170,000	430,000	1,278,000	1,771,500	2,239,000
Repayments of Advances from the Federal Home Loan Bank and other borrowings	(265,447)	(370,000)	(1,284,118)	(1,529,500)	(2,029,536)
Dividend paid	0	(40,000)	(40,000)	0	0
Proceeds from common stock issued - Class A	29,218	0	17,908	0	0
Repurchase of common stock - Class B	(28,465)	0	(17,908)	0	0
Net cash (used in) provided by financing activities	(239,192)	(22,768)	(336,405)	(62,393)	243,667
Net (decrease) increase in cash and cash equivalents	3,979	112,212	(67,735)	18,456	(3,293)
Cash and cash equivalents
Beginning of period	85,710	153,445	153,445	134,989	138,282
End of period	89,689		85,710	153,445
Supplemental disclosures of cash flow information
Cash paid for Interest	24,086	18,255	89,283	61,590	46,109
Cash paid for Income taxes	$ 385	$ 81	18,954	18,881	9,264
Noncash investing activities:
Loans transferred to other assets			925	319	5,545
Loans held for sale exchanged for securities			$ 0	$ 4,710	$ 4,659

Business, Basis of Presentation

Business, Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business, Basis of Presentation and Summary of Significant Accounting Policies	Business, Basis of Presentation and Summary of Significant Accounting Policies a) Business Mercantil Bank Holding Corporation (the “Company”), is a Florida corporation incorporated in 1985, which has operated since January 1987. The Company is a bank holding company registered under the Bank Holding Company Act of 1956, as a result of its 100% indirect ownership of Amerant Bank, N.A. (the “Bank”). The Company’s principal office is in the City of Coral Gables, Florida. The Bank is a member of the Federal Reserve Bank of Atlanta (“Federal Reserve ”) and the Federal Home Loan Bank of Atlanta (“FHLB”). The Bank has two principal subsidiaries, Amerant Investments, Inc. a securities broker-dealer (“Amerant Investments”), and Amerant Trust, N.A, a non-depository trust company (“Amerant Trust”). The Company is rebranding as “Amerant.” The Company’s principal subsidiaries have adopted this name and logo. The Company will use the Amerant brand and will officially change its corporate name upon approval at its annual shareholders’ meeting in June 2019. The Company’s Class A common stock, par value $0.10 per common share, and Class B common stock, par value $0.10 per common share, are listed and trade on the Nasdaq Global Select Market under the symbols “AMTB” and “AMTBB,” respectively. b) Initial Public Offering and Shares Repurchase On December 21, 2018, the Company completed an initial public offering (the “IPO”). For more information about the IPO, see Note 15 to our audited consolidated financial statements included in the Company’s annual report on Form 10-K filed with the U.S. Securities and Exchange Commission (the “SEC”) on April 1, 2019 (the “Form 10-K”). In March 2019, following the partial exercise of the over-allotment option by the IPO’s underwriters, and completion of certain private placements of shares of the Company’s Class A common stock, the Company repurchased the remaining shares of its Class B common stock held by Mercantil Servicios Financieros, C.A., or MSF, the Company’s former parent company. See Note 11 to these unaudited interim consolidated financial statements for more information about the private placements and the repurchase of Class B common stock previously held by MSF. c) Subsequent Events The effects of significant subsequent events, if any, have been recognized or disclosed in these unaudited interim consolidated financial statements. d) Basis of Presentation and Summary of Significant Accounting Policies The accompanying unaudited interim consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X of the SEC. Accordingly, they do not include all of the information and footnotes required for a fair statement of financial position, results of operations and cash flows in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”). These unaudited interim consolidated financial statements reflect all adjustments that are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. These adjustments are of a normal, recurring nature. Interim period operating results may not be indicative of the operating results for a full year or any other period. These unaudited interim consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements as of December 31, 2018 and 2017 and for each of the three years in the period ended December 31, 2018 and the accompanying footnote disclosures for the Company, which are included in the Form 10-K. For a complete summary of our significant accounting policies, please see Note 1 to the Company’s audited consolidated financial statements on the Form 10-K. Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates made by management include: (i) the determination of the allowance for loan losses; (ii) the fair values of securities and the reporting unit to which goodwill has been assigned during the annual goodwill impairment test; (iii) the cash surrender value of bank owned life insurance; and (iv) the determination of whether the amount of deferred tax assets will more likely than not be realized. Management believes that these estimates are appropriate. Actual results could differ from these estimates. Segment Reporting Prior to the second quarter of 2019, the Company had four reportable segments: Personal and Commercial Banking (“PAC”), Corporate LATAM, Treasury and Institutional. Results of these segments were presented on a managed basis. This structure was driven, among other things, by how the Company previously managed the business, how internal reporting was prepared and analyzed, and how management made decisions. In August 2019, the Company announced that due to changes in the structure of its internal organization that it would report its financial performance as a single operating segment beginning with the quarter ended June 30, 2019. As a result of these changes, all decisions, including those relating to loan growth and concentrations, deposit and other funding, market risk, credit risk, operational risk and pricing are now made after assessing their effects on the Company as a whole, using a single segment concept. Revisions In 2018, the Company determined to revise its presentation of loans by classes to correct for certain immaterial misclassifications in the presentation of loans by classes in the footnotes to the Company’s unaudited interim consolidated financial statements as of March 31, 2018. The Company assessed the impact of these misclassifications and determined they had no effect on the unaudited interim consolidated balance sheet as of March 31, 2018, the unaudited interim consolidated statements of operations and comprehensive income or the unaudited interim consolidated statement of cash flows for the three months ended March 31, 2018. The following tables show the effects of the correction of the misclassifications to the footnotes to the Company’s unaudited interim consolidated financial statements as of March 31, 2018. This change in classification is reflected in the footnotes to the unaudited interim consolidated financial statements as of March 31, 2019 and for the three months ended March 31, 2019 and 2018. Changes in the allocation of allowance for loan losses and its allocation by impairment methodology and the related investment in loans: As reported: Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 30,246 $ 33,731 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (864 ) 578 (691 ) 977 — Loans charged-off Domestic — (382 ) — (19 ) (401 ) International — — — (400 ) (400 ) Recoveries 34 832 — 53 919 Balances at end of the period $ 29,416 $ 34,759 $ 3,671 $ 4,272 $ 72,118 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,226 $ — $ — $ 2,226 Collectively evaluated 29,416 32,533 3,671 4,272 69,892 $ 29,416 $ 34,759 $ 3,671 $ 4,272 $ 72,118 Investment in loans, net of unearned income Individually evaluated $ 11,238 $ 15,055 $ — $ 342 $ 26,635 Collectively evaluated 2,699,872 2,243,345 416,292 564,306 5,923,815 $ 2,711,110 $ 2,258,400 $ 416,292 $ 564,648 $ 5,950,450 Changes in the allocation of allowance for loan losses and its allocation by impairment methodology and the related investment in loans: As revised: Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (821 ) 535 (691 ) 977 — Loans charged-off Domestic — (382 ) — (19 ) (401 ) International — — — (400 ) (400 ) Recoveries 34 832 — 53 919 Balances at end of the period $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,226 $ — $ — $ 2,226 Collectively evaluated 30,503 31,446 3,671 4,272 69,892 $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Investment in loans, net of unearned income Individually evaluated $ 11,238 $ 15,055 $ — $ 342 $ 26,635 Collectively evaluated 2,803,394 2,139,788 416,292 564,341 5,923,815 $ 2,814,632 $ 2,154,843 $ 416,292 $ 564,683 $ 5,950,450 Changes in the allocation of allowance for loan losses and its allocation by impairment methodology and the related investment in loans: Effects of change: Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 1,044 $ (1,044 ) $ — $ — $ — (Reversal of) provision for loan losses 43 (43 ) — — — Loans charged-off Domestic — — — — — International — — — — — Recoveries — — — — — Balances at end of the period $ 1,087 $ (1,087 ) $ — $ — $ — Allowance for loan losses by impairment methodology Individually evaluated $ — $ — $ — $ — $ — Collectively evaluated 1,087 (1,087 ) — — — $ 1,087 $ (1,087 ) $ — $ — $ — Investment in loans, net of unearned income Individually evaluated $ — $ — $ — $ — $ — Collectively evaluated 103,522 (103,557 ) — 35 — $ 103,522 $ (103,557 ) $ — $ 35 $ —	Business, Basis of Presentation and Summary of Significant Accounting Policies a) Business Mercantil Bank Holding Corporation (the “Company”), is a Florida corporation incorporated in 1985, which has operated since January 1987. The Company is a bank holding company registered under the Bank Holding Company Act of 1956, as a result of its 100% indirect ownership of Amerant Bank, N.A. (the “Bank”). The Company’s principal office is in the City of Coral Gables, Florida. The Bank is a member of the Federal Reserve Bank of Atlanta (“Federal Reserve ”) and the Federal Home Loan Bank of Atlanta (“FHLB”). The Bank has two principal subsidiaries, Amerant Investments, Inc., a securities broker-dealer (“Amerant Investments”), and Amerant Trust, N.A., a non-depository trust company (“Amerant Trust”). The Bank has been serving the communities in which it operates for almost 40 years. The Bank is headquartered in the City of Coral Gables, Florida and has 23 Banking Centers, including 15 located in South Florida and 8 in the Greater Houston area, Texas, as well as a loan production office in New York City, New York, and a loan production office recently opened in Dallas, Texas. As the main operating subsidiary of the Company, the Bank offers a wide variety of domestic, international, personal and commercial banking services. Investment, trust, fiduciary and wealth management services are provided through the Bank’s main operating subsidiaries Amerant Investments, Inc. and Amerant Trust, N.A. The Company, Mercantil Servicios Financieros, C.A. (“MSF” or the “former parent”), and various individuals as Voting Trustees, entered into a Voting Trust Agreement (the “Voting Trust”) in October 2008. On July 24, 2018, the Voting Trust was terminated. The Company is now the sole shareholder of Mercantil Florida Bancorp, Inc. and the indirect owner of 100% of the Bank. On August 8, 2018, the Company became subject to the reporting requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934 (the “Securities Act”). On October 24, 2018, the Company announced it is rebranding as “Amerant.” The Company’s principal subsidiaries have adopted this name and logo. The Company will use the Amerant brand and will officially change its corporate name upon approval at its annual shareholders’ meeting in 2019. b) Spin-off As of December 31, 2017 the Company was a wholly owned subsidiary of MSF. On March 15, 2018, MSF transferred ownership of 100% of the Company Shares to a non-discretionary common law, grantor trust formed pursuant to a Distribution Agreement among MSF, the Company and an unaffiliated trustee dated as of March 12, 2018, and governed by the laws of the State of Florida (the “Distribution Trust”). The Company and MSF are parties to an Amended and Restated Separation and Distribution Agreement dated as of June 12, 2018 that provided for the spin-off (the “Spin-off”) of the Company from MSF. The Distribution Trust was established by MSF and the Company pursuant to a Distribution Trust Agreement, as amended, with a Texas trust company, unaffiliated with MSF, as trustee. The Distribution Trust held 80.1% of the Company Shares (the “Distributed Shares”) for the benefit of MSF’s Class A and Class B common shareholders of record (“Record Holders”) on April 2, 2018 (“Record Date”). The remaining 19.9% of the Company Shares were held in the Distribution Trust for the benefit of MSF (the “Retained Shares”). The Distributed Shares were distributed to MSF shareholders on August 10, 2018 (the “Distribution”). As a result of the Distribution, the Company became a separate company and its common stock was listed on the Nasdaq Global Select Market on August 13, 2018. The Distribution Trust held the Retained Shares pending their disposition by MSF. c) Initial Public Offering On December 21, 2018, the Company completed an initial public offering (the “IPO”). See Note 15 to our consolidated financial statements for more information about the IPO. At December 31, 2018, MSF beneficially owned less than 5% of all of the Company’s outstanding shares of common stock and the Board of Governors of the Federal Reserve System determined that MSF no longer controlled the Company for purposes of the Bank Holding Company Act of 1956. In December 2018 in connection with the IPO, the Company repurchased approximately $1.4 million shares of Class B common stock from MSF. In March 2019, following the partial exercise of the over-allotment option by the IPO’s underwriters, and completion of certain private placements of shares of the Company’s Class A common stock, the Company repurchased the remaining shares of Class B common stock held by MSF. See Note 15 to our consolidated financial statements for more information about the private placements and the repurchase of Retained Shares previously held by MSF. d) Subsequent Events The effects of significant subsequent events, if any, have been recognized or disclosed in these consolidated financial statements. e) Basis of Presentation and Summary of Significant Accounting Policies The following is a description of the significant accounting policies and practices followed by the Company in the preparation of the accompanying consolidated financial statements. These policies conform with generally accepted accounting principles in the United States (U.S. GAAP). Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Recasting of Certain Prior Period Information due to Changes in Segment Reporting Prior to the second quarter of 2019, the Company had four reportable segments: Personal and Commercial Banking (“PAC”), Corporate LATAM, Treasury and Institutional. Results of these segments were presented on a managed basis. This structure was driven, among other things, by how the Company previously managed the business, how internal reporting was prepared and analyzed, and how management made decisions. In August 2019, the Company announced that due to changes in the structure of its internal organization that it would report its financial performance as a single operating segment beginning with the quarter ended June 30, 2019. As a result of these changes, all decisions, including those relating to loan growth and concentrations, deposit and other funding, market risk, credit risk, operational risk and pricing are now made after assessing their effects on the Company as a whole, using a single segment concept. In this Form 8-K, we have recast certain previously reported information to reflect that the Company reports its financial performance as a single operating segment. This change primarily impacted Note 21 - Segment Information, with no impact on consolidated net income or cash flows. Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates made by management include: i) the determination of the allowance for loan losses; (ii) the fair values of securities and the reporting unit to which goodwill has been assigned during the annual goodwill impairment test; (iii) the cash surrender value of bank owned life insurance; and (iv) the determination of whether the amount of deferred tax assets will more likely than not be realized. Management believes that these estimates are appropriate. Actual results could differ from these estimates. Income Recognition Interest income is generally recognized on the accrual basis using the interest method. Non-refundable loan origination fees, net of direct costs of originating or acquiring loans, as well as loan purchase premiums and discounts, are deferred and amortized over the term of the related loans as adjustments to interest income using the level yield method. Purchase premiums and discounts on debt securities are amortized as adjustments to interest income over the estimated lives of the securities using the level yield method. Brokerage and advisory activities include brokerage commissions and advisory fees. Brokerage commissions earned are related to the dollar amount of trading volume of customers’ transactions. Commissions and related clearing expenses are recorded on a trade-date basis as securities transactions occur. Advisory fees are derived from investment advisory fees and account administrative services. Investment advisory fees are recorded as earned on a pro rata basis over the term of the contracts, based on a percentage of the average value of assets managed during the period. These fees are assessed and collected at least quarterly. Account administrative fees are charged to customers for the maintenance of their accounts and are earned and collected on a quarterly basis. Fiduciary activities fee income is recognized as earned on a pro rata basis over the term of contracts. Card servicing fees include credit card issuance and credit and debit card interchange fees. Credit card issuance fees are generally recognized over the period in which the cardholders are entitled to use the cards. Interchange fees are recognized when earned. Trade finance servicing fees, which primarily include commissions on letters of credit, are generally recognized over the service period on a straight line basis. Deposits and services fees include service charges on deposit accounts, fees for banking services provided to customers including wire transfers, overdrafts and non-sufficient funds. Revenue is generally recognized in accordance with published deposit account agreements for customer accounts or when fixed and determinable per contractual agreements. Data processing, rental income and fees for other services to related parties are recognized as the services are provided in accordance with the terms of the service agreements. Earnings per Share Basic earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of common shares outstanding during each period. Unvested shares of restricted stock are excluded from the basic earnings per share computation. Diluted net income per common share reflects the number of additional common stock that would have been outstanding if the dilutive potential common stock had been issued. Dilutive potential common stock consist of unvested shares of restricted stock outstanding during the period. The dilutive effect of potential common stock is calculated by applying the treasury stock method. The latter assumes dilutive potential common stock are issued and outstanding and the proceeds from the exercise, are used to purchase common stock at the average market price during the period. The difference between the numbers of dilutive potential common stock issued and the number of shares purchased is included as incremental shares in the denominator to compute diluted net income per common stock. Dilutive potential common stock are excluded from the diluted earnings per share computation in the period in which the effect is anti-dilutive. Changes in the number of shares outstanding as a result of stock dividends, stock splits, stock exchanges or reverse stock splits are given effect retroactively for all periods presented to reflect those changes in capital structure. Stock-based Compensation The Company may grant share-based compensation and other related awards to its non-employee directors, officers, employees and certain consultants. Compensation cost is measured based on the estimated fair value of the award at the grant date and recognized in earnings on a straight -line basis over the requisite service period or vesting period. The fair value of the unvested shares of restricted stock is based on the market price of the Company’s Class A common stock at the date of the grant. Advertising Expenses Advertising expenses are expensed as incurred and are included in other noninterest expenses. Offering Expenses Specific, non-reimbursable, incremental costs directly attributable to a proposed or actual securities offerings are deferred and charged against the gross proceeds of the offering. Cash and Cash Equivalents The Company has defined as cash equivalents those highly liquid instruments purchased with an original maturity of three months or less and include cash and cash due from banks, federal funds sold and deposits with banks. The Company must comply with federal regulations requiring the maintenance of minimum reserve balances against its deposits. At December 31, 2018 and 2017, these reserve balances amounted to approximately $0.2 million and $1.2 million , respectively. Securities The Company classifies its investments in securities as available for sale and held to maturity. Securities classified as available for sale are carried at fair value with unrealized gains and losses included in accumulated other comprehensive income (“AOCI”) in stockholders’ equity on an after-tax basis. Securities classified as held to maturity are securities the Company has both the ability and intent to hold until maturity and are carried at amortized cost. Investments in stock issued by the Federal Reserve and Federal Home Loan Bank of Atlanta (“FHLB”) are stated at their original cost, which approximates their realizable value. Realized gains and losses from sales of securities are recorded on the trade date and are determined using the specific identification method. Securities purchased are recorded on the consolidated balance sheets as of the trade date. Receivables and payables to and from clearing organizations relating to outstanding transactions are included in other assets or other liabilities. At December 31, 2018 and 2017 securities receivables amounted to $3.5 million and $6.5 million , respectively. The Company considers an investment security to be impaired when a decline in fair value below the amortized cost basis is other-than-temporary. When an investment security is considered to be other-than-temporarily impaired, the cost basis of the individual investment security is written down through earnings by an amount that corresponds to the credit component of the other-than-temporary impairment. The amount of the other-than-temporary impairment that corresponds to the noncredit component of the other-than-temporary impairment is recorded in AOCI and is associated with securities which the Company does not intend to sell and it is more likely than not that the Company will not be required to sell the securities prior to the recovery of its fair value. The Company estimates the credit component of other-than-temporary impairment using a discounted cash flow model. The Company estimates the expected cash flows of the underlying collateral using third party vendor models that incorporate management’s best estimate of current key assumptions, such as default rates, loss severity and prepayment rates (based on historical performance and stress test scenarios). Assumptions used can vary widely from security to security and are influenced by such factors as current debt service coverage ratio, historical prepayment rates, expected prepayment rates, and loans’ current interest rates. The Company then uses, as it deems appropriate, a third party vendor to determine how the underlying collateral cash flows will be distributed to each security. The present value of an impaired debt security results from estimating its future cash flows, discounted at the security’s effective interest rate. The Company expects to recover the remaining noncredit related unrealized losses included as a component of AOCI. Loans Held for Sale Loans are transferred into the held for sale classification at the lower of carrying amount or fair value when they are specifically identified for sale and a formal plan exists to sell them. Loans Loans represent extensions of credit which the Company has the intent and ability to hold for the foreseeable future or until maturity or payoff. These extensions of credit consist of commercial real estate loans (including land acquisition, development and construction loans), single-family residential loans, commercial loans, loans to financial institutions and acceptances, and consumer loans. Amounts included in the loan portfolio are stated at the amount of unpaid principal, reduced by unamortized net deferred loan fees and origination costs and an allowance for loan losses. Unamortized net deferred loan fees and origination costs amounted to $7.1 million and $7.4 million at December 31, 2018 and 2017, respectively. A loan is placed in nonaccrual status when management believes that collection in full of the principal amount of the loan or related interest is in doubt. Management considers that collectability is in doubt when any of the following factors are present, among others: (1) there is a reasonable probability of inability to collect principal, interest or both, on a loan for which payments are current or delinquent for less than ninety days; or (2) when a required payment of principal, interest or both is delinquent for ninety days or longer, unless the loan is considered well secured and in the process of collection in accordance with regulatory guidelines. Once a loan to a single borrower has been placed in nonaccrual status, management reviews all loans to the same borrower to determine their appropriate accrual status. When a loan is placed in nonaccrual status, accrual of interest and amortization of net deferred loan fees or costs are discontinued, and any accrued interest receivable is reversed against interest income. Payments received on a loan in nonaccrual status are generally applied to its outstanding principal amount, unless there are no doubts on the full collection of the remaining recorded investment in the loan. When there are no doubts on the full collection of the remaining recorded investment in the loan, and there is sufficient documentation to support the collectability of that amount, payments of interest received may be recorded as interest income. A loan in nonaccrual status is returned to accrual status when none of the conditions noted when first placed in nonaccrual status are currently present, none of its principal and interest is past due, and management believes there are reasonable prospects of the loan performing in accordance with its terms. For this purpose, management generally considers there are reasonable prospects of performance in accordance with the loan terms when at least six months of principal and interest payments or principal curtailments have been received, and current financial information of the borrower demonstrates that performance will continue into the near future. The total outstanding principal amount of a loan is reported as past due thirty days following the date of a missed scheduled payment, based on the contractual terms of the loan. Loans which have been modified because the borrowers were experiencing financial difficulty and the Company, for economic or legal reasons related to the debtors’ financial difficulties, granted a concession to the debtors that it would not have otherwise considered, are accounted for as troubled debt restructurings (“TDR”). Allowance for Loan Losses The allowance for loan losses represents an estimate of the current amount of principal that is probable the Company will be unable to collect given facts and circumstances as of the evaluation date, and includes amounts arising from loans individually and collectively evaluated for impairment. These estimated amounts are recorded through a provision for loan losses charged against income. Management periodically evaluates the adequacy of the allowance for loan losses to maintain it at a level believed reasonable to provide for recognized and unrecognized but inherent losses in the loan portfolio. The Company uses the same methods used to determine the allowance for loan losses, to assess any reserves needed for off-balance sheet credit risks such as unfunded loan commitments and contingent obligations on letters of credit. These reserves for off-balance sheet credit risks are presented in the liabilities section in the consolidated balance sheets. The Company develops and documents its methodology to determine the allowance for loan losses at the portfolio segment level. The Company determines its loan portfolio segments based on the type of loans it carries and their associated risk characteristics. The Company’s loan portfolio segments are: Real Estate, Commercial, Financial Institutions, Consumer and Other. Loans in these portfolio segments have distinguishing borrower needs and differing risks associated with each product type. Real estate loans include commercial loans secured by real estate properties. Commercial loans secured by non-owner occupied real estate properties are generally granted to finance the acquisition or operation of commercial real estate properties, with terms similar to the properties’ useful lives or the operating cycle of the businesses. The main source of repayment of these real estate loans is derived from cash flows or conversion of productive assets and not from the income generated by the disposition of the property held as collateral. The main repayment source of loans granted to finance land acquisition, development and construction projects is generally derived from the disposition of the properties held as collateral, with the repayment capacity of the borrowers and any guarantors considered as alternative sources of repayment. Commercial loans correspond to facilities established for specific business purposes such as financing working capital and capital improvements projects and asset-based lending, among others. These may be loan commitments, uncommitted lines of credit to qualifying customers, short term (one year or less) or longer term credit facilities, and may be secured, unsecured or partially secured. Terms on commercial loans generally do not exceed five years, and exceptions are documented. Commercial loans secured by owner-occupied real estate properties are generally granted to finance the acquisition or operation of commercial real estate properties, with terms similar to the properties’ useful lives or the operating cycle of the businesses. The main source of repayment of these commercial real estate loans is derived from cash flows and not from the income generated by the disposition of the property held as collateral. Commercial loans to borrowers in similar businesses or products with similar characteristics or specific credit requirements are generally evaluated under a standardized commercial credit program. Commercial loans outside the scope of those programs are evaluated on a case by case basis, with consideration of any exposure under an existing commercial credit program. Loans to financial institutions and acceptances are facilities granted to fund certain transactions classified according to their risk level, and primarily include trade financing facilities through letters of credits, bankers’ acceptances, pre- and post-export financing, and working capital loans, among others. Loans in this portfolio segment are generally granted for terms not exceeding three years and on an unsecured basis under the limits of an existing credit program, primarily to large financial institutions in Latin America which the Company believes are of high quality. Prior to approval, management also considers cross-border and portfolio limits set forth in its programs and credit policies. Consumer and other loans are retail open-end and closed-end credits extended to individuals for household, family and other personal expenditures. These loans include loans to individuals secured by their personal residence, including first mortgage, home equity and home improvement loans as well as revolving credit card agreements. Because these loans generally consist of a large number of relatively small-balance, homogeneous loans for each type, their risks are generally evaluated collectively. An individual loan is considered impaired when it is probable that the Company will be unable to collect all amounts due, including both principal and interest, according to the contractual terms of the loan agreement. The Company generally considers as impaired all loans in nonaccrual status, and other loans classified in accordance with an internal risk grading system exceeding a defined threshold when it is probable that an impairment exists and the amount of the potential impairment is reasonably estimable. To determine when it is probable that an impairment exists, the Company considers the extent to which a loan may be inadequately protected by the current net worth and paying capacity of the borrower or any guarantor, or by the current value of the collateral. When a loan is considered impaired, the potential impairment is measured as the excess of the carrying value of the loan over the present value of expected future cash flows at the measurement date, or the fair value of the collateral in the case where the loan is considered collateral-dependent. If the amount of the present value of the loan’s expected future cash flows exceeds the loan’s carrying amount, the loan is still considered impaired but no impairment is recorded. The present value of an impaired loan results from estimating its future cash flows, discounted at the loan’s effective interest rate. In the case of loans considered collateral-dependent, which are generally certain real estate loans for which repayment is expected to be provided solely by the operation or sale of the underlying collateral, the potential impairment is measured based on the fair value of the asset pledged as collateral. The allowance for loan losses on loans considered TDR is generally determined by discounting the restructured cash flows by the original effective interest rate on the loan. Loans that do not meet the criteria of an individually impaired loan are collectively evaluated for impairment. These loans include large groups of smaller homogeneous loan balances, such as loans in the consumer and other loan portfolio segment, and all other loans that have not been individually identified as impaired. This group of collective loans is evaluated for impairment based on measures of historical losses associated with loans within their respective portfolio segments adjusted by a variety of qualitative factors. These qualitative factors incorporate the most recent data reflecting current economic conditions, industry performance trends or obligor concentrations within each portfolio segment, among other factors. Other adjustments may be made to the allowance for loans collectively evaluated for impairment based on any other pertinent information that management considers may affect the estimation of the allowance for loan losses, including a judgmental assessment of internal and external influences on credit quality that are not fully reflected in historical loss or their risk rating data. The measures of historical losses and the related qualitative adjustments are updated quarterly and semi-annually, respectively, to incorporate the most recent loan loss data reflecting current economic conditions. Loans to borrowers that are domiciled in foreign countries, primarily loans in the Consumer and Financial Institutions portfolio segments, are also evaluated for impairment by assessing the probability of additional losses arising from the Company’s exposure to transfer risk. The Company defines transfer risk exposure as the possibility that a loan obligation cannot be serviced in the currency of payment (U.S. Dollars) because the borrower’s country of origin may not have sufficient available currency of payment or may have put restraints on its availability, such as currency controls. To determine an individual country’s transfer risk probability, the Company assigns numerical values corresponding to the perceived performance of that country in certain macroeconomic, social and political factors generally considered in the banking industry for evaluating a country’s transfer risk. A defined country’s transfer risk probability is assigned to that country based on an average of the individual scores given to those factors, calculated using an interpolation formula. The results of this evaluation are also updated semi-annually. Loans in the Real Estate, Commercial and Financial Institutions portfolio segments are charged off against the allowance for loan losses when they are considered uncollectable. These loans are considered uncollectable when a loss becomes evident to management, which generally occurs when the following conditions are present, among others: (1) a loan or portions of a loan are classified as “loss” in accordance with the internal risk grading system; (2) a collection attorney has provided a written statement indicating that a loan or portions of a loan are considered uncollectible; and (3) the carrying value of a collateral-dependent loan exceeds the appraised value of the asset held as collateral. Consumer and other retail loans are charged off against the allowance for loan losses at the earlier of (1) when management becomes aware that a loss has occurred, or (2) when closed-end retail loans become past due 120 days or open-end retail loans become past due 180 days from the contractual due date. For open and closed-end retail loans secured by residential real estate, any outstanding loan balance in excess of the fair value of the property, less cost to sell, is charged off no later than when the loan is 180 days past due from the contractual due date. Consumer and other retail loans may not be charged off when management can clearly document that a past due loan is well secured and in the process of collection such that collection will occur regardless of delinquency status in accordance with regulatory guidelines applicable to these types of loans. Recoveries on loans represent collections received on amounts that were previously charged off against the allowance for loan losses. Recoveries are credited to the allowance for loan losses when received, to the extent of the amount previously charged off against the allowance for loan losses on the related loan. Any amounts collected in excess of this limit are first recognized as interest income, then as a reduction of collection costs, and then as other income. Transfers of Financial Assets Transfers of financial assets are accounted for as sales or purchases when control over the assets has been surrendered by the transferor. Control over transferred assets is deemed to be surrendered when the assets have been isolated from the transferor, the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and the transferor does not maintain effective control over the transferred assets. Premises and Equipment, Net Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is computed on the straight-line basis over the estimated useful lives of the related assets. Leasehold improvements are amortized over the remaining term of the lease. Repairs and maintenance are charged to operations as incurred; renewals, betterments and interest during construction are capitalized. Gains or losses on sales of premises and equipment are recorded as other noninterest income or noninterest expense, respectively, at the date of sale. Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. For purposes of recognition and measurement of an impairment loss, when the independent and identifiable cash flow of a single asset may not be determinable, the long-lived asset may be grouped with other assets of like cash flows. Recoverability of an asset or group of assets to be held and used is measured by comparing the carrying amount with future undiscounted net cash flows expected to be generated by the asset or group of assets. If an asset is considered impaired, the impairment recognized is generally measured by the amount by which the carrying amount of the asset or group exceeds its fair value. Bank Owned Life Insurance Bank owned life insurance policies (“BOLI”) are recorded at the cash surrender val

Interest Earning Deposits with

Interest Earning Deposits with Banks	12 Months Ended
	Dec. 31, 2018
Cash and Cash Equivalents [Abstract]
Interest Earning Deposits with Banks	Interest Earning Deposits with Banks At December 31, 2018 and 2017 interest earning deposits with banks are comprised of deposits with the Federal Reserve of approximately $60 million and $109 million , respectively. At December 31, 2018 and 2017, the average interest rate on these deposits was approximately 1.88% and 1.10% , respectively. These deposits mature within one year.

Securities

Securities	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Securities	Securities Amortized cost and approximate fair values of securities available for sale are summarized as follows: March 31, 2019 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 899,571 $ 4,687 $ (13,800 ) $ 890,458 Corporate debt securities 258,421 1,089 (1,168 ) 258,342 U.S. government agency debt securities 218,813 362 (3,839 ) 215,336 Municipal bonds 162,123 2,295 (430 ) 163,988 Mutual funds 24,267 — (800 ) 23,467 Commercial paper — — — — $ 1,563,195 $ 8,433 $ (20,037 ) $ 1,551,591 December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 840,760 $ 2,197 $ (22,178 ) $ 820,779 Corporate debt securities 357,602 139 (5,186 ) 352,555 U.S. government agency debt securities 221,682 187 (4,884 ) 216,985 Municipal bonds 162,438 390 (2,616 ) 160,212 Mutual funds 24,266 — (1,156 ) 23,110 Commercial paper 12,448 — (38 ) 12,410 $ 1,619,196 $ 2,913 $ (36,058 ) $ 1,586,051 At March 31, 2019 and December 31, 2018 , the Company had no foreign sovereign debt securities. The Company’s securities available for sale with unrealized losses that are deemed temporary, aggregated by the length of time that individual securities have been in a continuous unrealized loss position, are summarized below: March 31, 2019 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 74,413 $ (1,995 ) $ 524,470 $ (11,805 ) $ 598,883 $ (13,800 ) Corporate debt securities 72,106 (365 ) 75,776 (803 ) 147,882 (1,168 ) Municipal bonds — — 48,859 (430 ) 48,859 (430 ) U.S. government agency debt securities 43,198 (436 ) 136,260 (3,403 ) 179,458 (3,839 ) Mutual funds — — 23,220 (800 ) 23,220 (800 ) Commercial paper — — — — — — $ 189,717 $ (2,796 ) $ 808,585 $ (17,241 ) $ 998,302 $ (20,037 ) December 31, 2018 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 90,980 $ (2,995 ) $ 608,486 $ (19,183 ) $ 699,466 $ (22,178 ) Corporate debt securities 243,667 (3,800 ) 75,762 (1,386 ) 319,429 (5,186 ) Municipal bonds 63,580 (939 ) 133,886 (3,945 ) 197,466 (4,884 ) U.S. government agency debt securities 1,449 (6 ) 94,331 (2,610 ) 95,780 (2,616 ) Mutual funds — — 22,865 (1,156 ) 22,865 (1,156 ) Commercial paper 12,410 (38 ) — — 12,410 (38 ) $ 412,086 $ (7,778 ) $ 935,330 $ (28,280 ) $ 1,347,416 $ (36,058 ) At March 31, 2019 and December 31, 2018 , debt securities issued or guaranteed by U.S. government-sponsored entities and agencies held by the Company were issued by institutions which the Company believes to possess little credit risk. The Company does not consider these securities to be other-than-temporarily impaired because the decline in fair value is attributable to changes in interest rates and investment securities markets, generally, and not credit quality. The Company does not have the intent to sell these debt securities and it is more likely than not that it will not be required to sell the securities before their anticipated recovery. Unrealized losses on municipal and corporate debt securities, at March 31, 2019 and December 31, 2018 , are attributable to changes in interest rates and investment securities markets, generally, and as a result, temporary in nature. The Company does not consider these securities to be other-than-temporarily impaired because the issuers of these debt securities are considered to be high quality, and management does not intend to sell these investments and it is more likely than not that it will not be required to sell these investments before their anticipated recovery. Amortized cost and approximate fair values of securities held to maturity, are summarized as follows: March 31, 2019 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 81,088 $ 79 $ (1,635 ) $ 79,532 U.S. Government agency debt securities 2,821 22 — 2,843 $ 83,909 $ 101 $ (1,635 ) $ 82,375 December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 82,326 $ — $ (3,889 ) $ 78,437 U.S. Government agency debt securities 2,862 — (49 ) 2,813 $ 85,188 $ — $ (3,938 ) $ 81,250 Contractual maturities of securities at March 31, 2019 are as follows: Available for Sale Held to Maturity (in thousands) Amortized Estimated Amortized Estimated Within 1 year $ 34,856 $ 34,769 $ — $ — After 1 year through 5 years 239,679 239,297 — — After 5 years through 10 years 172,190 172,421 — — After 10 years 1,092,203 1,081,637 83,909 82,375 No contractual maturities 24,267 23,467 — — $ 1,563,195 $ 1,551,591 $ 83,909 $ 82,375	Securities Amortized cost and approximate fair values of securities available for sale are summarized as follows: December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 840,760 $ 2,197 $ (22,178 ) $ 820,779 Corporate debt securities 357,602 139 (5,186 ) 352,555 U.S. government agency debt securities 221,682 187 (4,884 ) 216,985 Municipal bonds 162,438 390 (2,616 ) 160,212 Mutual funds 24,266 — (1,156 ) 23,110 Commercial paper 12,448 — (38 ) 12,410 $ 1,619,196 $ 2,913 $ (36,058 ) $ 1,586,051 December 31, 2017 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 889,396 $ 1,784 $ (15,514 ) $ 875,666 Corporate debt securities 310,781 3,446 (835 ) 313,392 U.S. government agency debt securities 293,908 870 (3,393 ) 291,385 Municipal bonds 179,524 2,343 (1,471 ) 180,396 Mutual funds 24,262 — (645 ) 23,617 U.S. treasury securities 2,700 2 (1 ) 2,701 $ 1,700,571 $ 8,445 $ (21,859 ) $ 1,687,157 At December 31, 2018 and 2017 , the Company had no foreign sovereign debt securities. The Company’s investment securities available for sale with unrealized losses that are deemed temporary, aggregated by length of time that individual securities have been in a continuous unrealized loss position, are summarized below: December 31, 2018 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 90,980 $ (2,995 ) $ 608,486 $ (19,183 ) $ 699,466 $ (22,178 ) Corporate debt securities 243,667 (3,800 ) 75,762 (1,386 ) 319,429 (5,186 ) U.S. government agency debt securities 63,580 (939 ) 133,886 (3,945 ) 197,466 (4,884 ) Municipal bonds 1,449 (6 ) 94,331 (2,610 ) 95,780 (2,616 ) Mutual funds — — 22,865 (1,156 ) 22,865 (1,156 ) Commercial paper 12,410 (38 ) — — 12,410 (38 ) $ 412,086 $ (7,778 ) $ 935,330 $ (28,280 ) $ 1,347,416 $ (36,058 ) December 31, 2017 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 333,232 $ (2,956 ) $ 485,555 $ (12,558 ) $ 818,787 $ (15,514 ) U.S. government agency debt securities 92,138 (728 ) 128,316 (2,665 ) 220,454 (3,393 ) Municipal bonds 4,895 (8 ) 76,003 (1,463 ) 80,898 (1,471 ) Corporate debt securities 94,486 (751 ) 3,694 (84 ) 98,180 (835 ) Mutual funds — — 23,375 (645 ) 23,375 (645 ) U.S. treasury securities — — 2,199 (1 ) 2,199 (1 ) $ 524,751 $ (4,443 ) $ 719,142 $ (17,416 ) $ 1,243,893 $ (21,859 ) At December 31, 2018 and 2017 debt securities issued or guaranteed by U.S. government-sponsored entities and agencies held by the Company were issued by institutions which the Company believes to possess little credit risk. The Company does not consider these securities to be other-than-temporarily impaired because the decline in fair value is attributable to changes in interest rates and investment securities markets, generally, and not credit quality. The Company does not have the intent to sell these debt securities and it is more likely than not that it will not be required to sell the securities before their anticipated recovery. Unrealized losses on municipal and corporate debt securities, at December 31, 2018 and 2017 , are attributable to changes in interest rates and investment securities markets, generally, and as a result, temporary in nature. The Company does not consider these securities to be other-than-temporarily impaired because the issuers of these debt securities are considered to be high quality, and management does not intend to sell these investments and it is more likely than not that it will not be required to sell these investments before their anticipated recovery. Amortized cost and approximate fair values of securities held to maturity, are summarized as follows: December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 82,326 $ — $ (3,889 ) $ 78,437 U.S. Government agency debt securities 2,862 — (49 ) 2,813 $ 85,188 $ — $ (3,938 ) $ 81,250 December 31, 2017 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 86,826 $ 47 $ (441 ) $ 86,432 U.S. Government agency debt securities 3,034 — — 3,034 $ 89,860 $ 47 $ (441 ) $ 89,466 Contractual maturities of securities at December 31, 2018 are as follows: Available for Sale Held to Maturity (in thousands) Amortized Estimated Amortized Estimated Within 1 year $ 54,477 $ 54,306 $ — $ — After 1 year through 5 years 330,024 325,752 — — After 5 years through 10 years 166,152 163,039 — — After 10 years 1,044,277 1,019,844 85,188 81,250 No contractual maturities 24,266 23,110 — — $ 1,619,196 $ 1,586,051 $ 85,188 $ 81,250 Actual maturities of investment securities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without prepayment penalties. Proceeds from sales and calls of securities available for sale in 2018 and 2017 were approximately $67 million and $393 million , respectively, with gross realized gains of $0.5 million and gross realized losses of $1.4 million in 2018 (gross realized gains of $2.6 million and gross realized losses of $4.2 million in 2017). At December 31, 2018 and 2017 , securities available for sale with a fair value of approximately $50 million and $246 million , respectively, were pledged as collateral. In 2018, these securities were pledged as collateral to secure sweep accounts. In 2017, these securities were pledged as collateral to secure advances from the FHLB and sweep accounts.

Loans

Loans	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Loans	Loans The loan portfolio consists of the following loan classes: (in thousands) March 31, December 31, Real estate loans Commercial real estate Nonowner occupied $ 1,852,903 $ 1,809,356 Multi-family residential 878,239 909,439 Land development and construction loans 291,416 326,644 3,022,558 3,045,439 Single-family residential 535,306 533,481 Owner occupied 801,856 777,022 4,359,720 4,355,942 Commercial loans 1,239,525 1,380,428 Loans to financial institutions and acceptances 27,985 68,965 Consumer loans and overdrafts 107,208 114,840 $ 5,734,438 $ 5,920,175 The amounts above include loans under syndication facilities of approximately $640 million and $807 million at March 31, 2019 and December 31, 2018 , respectively, which include Shared National Credit facilities and agreements to enter into credit agreements among other lenders (club deals), and other agreements. The following tables summarize international loans by country, net of loans fully collateralized with cash of approximately $18.4 million and $19.5 million at March 31, 2019 and December 31, 2018 , respectively. March 31, 2019 (in thousands) Venezuela Others (1) Total Real estate loans Single-family residential (2) $ 124,772 $ 6,525 $ 131,297 Commercial loans — 63,061 63,061 Loans to financial institutions and acceptances — 8,000 8,000 Consumer loans and overdrafts (3) 25,763 8,228 33,991 $ 150,535 $ 85,814 $ 236,349 __________________ (1) Loans to borrowers in fifteen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit to customers with deposits with the Bank. Charging privileges for Venezuela resident card holders are suspended when the cardholders’ average deposits decline below the outstanding credit balance. At the beginning of 2018, the Company changed the monitoring of such balances from quarterly to monthly. The Company determined to discontinue its international credit cards in April 2019. December 31, 2018 (in thousands) Venezuela Others (1) Total Real estate loans Single-family residential (2) $ 128,971 $ 6,467 $ 135,438 Commercial loans — 73,636 73,636 Loans to financial institutions and acceptances — 49,000 49,000 Consumer loans and overdrafts (3) 28,191 13,494 41,685 $ 157,162 $ 142,597 $ 299,759 __________________ (1) Loans to borrowers in seventeen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit to customers with deposits with the Bank. Charging privileges for Venezuela resident card holders are suspended when the cardholders’ average deposits decline below the outstanding credit balance. At the beginning of 2018, the Company changed the monitoring of such balances from quarterly to monthly. The age analysis of the loan portfolio by class, including nonaccrual loans, as of March 31, 2019 and December 31, 2018 are summarized in the following tables: March 31, 2019 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,852,903 $ 1,852,903 $ — $ — $ — $ — $ — $ — Multi-family residential 878,239 877,574 — 665 — 665 665 — Land development and construction loans 291,416 291,416 — — — — — — 3,022,558 3,021,893 — 665 — 665 665 — Single-family residential 535,306 523,172 7,802 921 3,411 12,134 6,514 — Owner occupied 801,856 799,187 408 1,880 381 2,669 5,192 — 4,359,720 4,344,252 8,210 3,466 3,792 15,468 12,371 — Commercial loans 1,239,525 1,234,890 3,151 399 1,085 4,635 7,361 — Loans to financial institutions and acceptances 27,985 27,985 — — — — — — Consumer loans and overdrafts 107,208 105,434 587 434 753 1,774 37 749 $ 5,734,438 $ 5,712,561 $ 11,948 $ 4,299 $ 5,630 $ 21,877 $ 19,769 $ 749 December 31, 2018 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,809,356 $ 1,809,356 $ — $ — $ — $ — $ — $ — Multi-family residential 909,439 909,439 — — — — — — Land development and construction loans 326,644 326,644 — — — — — — 3,045,439 3,045,439 — — — — — — Single-family residential 533,481 519,730 7,910 2,336 3,505 13,751 6,689 419 Owner occupied 777,022 773,876 2,800 160 186 3,146 4,983 — 4,355,942 4,339,045 10,710 2,496 3,691 16,897 11,672 419 Commercial loans 1,380,428 1,378,022 704 1,062 640 2,406 4,772 — Loans to financial institutions and acceptances 68,965 68,965 — — — — — — Consumer loans and overdrafts 114,840 113,227 474 243 896 1,613 35 884 $ 5,920,175 $ 5,899,259 $ 11,888 $ 3,801 $ 5,227 $ 20,916 $ 16,479 $ 1,303 At March 31, 2019 and December 31, 2018 , loans with an outstanding principal balance of $1,289 million and $1,680 million , respectively, were pledged as collateral to secure advances from the FHLB.	Loans The loan portfolio consists of the following loan classes: (in thousands) December 31, December 31, Real estate loans Commercial real estate Nonowner occupied $ 1,809,356 $ 1,713,104 Multi-family residential 909,439 839,709 Land development and construction loans 326,644 406,940 3,045,439 2,959,753 Single-family residential 533,481 512,754 Owner-occupied 777,022 610,386 4,355,942 4,082,893 Commercial loans 1,380,428 1,354,755 Loans to financial institutions and acceptances 68,965 497,626 Consumer loans and overdrafts 114,840 130,951 $ 5,920,175 $ 6,066,225 The amounts in the table above include loans under syndication facilities for approximately $807 million and $989 million at December 31, 2018 and 2017 , respectively, which include Shared National Credit facilities and agreements to enter into credit agreements among other lenders (club deals), and other agreements. These loans are primarily designed for providing working capital to certain qualified domestic and international commercial entities meeting our credit quality criteria and concentration limits, and approved in accordance with credit policies. While seeking diversification of our loan portfolio, the Company is dependent mostly on the economic conditions that affect South Florida, greater Houston and the greater New York City area, especially the five New York City boroughs. Diversification is managed through policies with limitations for exposure to individual or related debtors and for country risk exposure. The following tables summarize international loans by country, net of loans fully collateralized with cash of approximately $19.5 million and $31.9 million at December 31, 2018 and 2017 , respectively. December 31, 2018 (in thousands) Venezuela Others (1) Total Real estate loans Single-family residential (2) $ 128,971 $ 6,467 $ 135,438 Loans to financial institutions and acceptances — 49,000 49,000 Commercial loans — 73,636 73,636 Consumer loans and overdrafts (3) 28,191 13,494 41,685 $ 157,162 $ 142,597 $ 299,759 __________________ (1) Loans to borrowers in seventeen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit to customers with deposits with the Bank. Charging privileges for Venezuela residents card holders are suspended when the cardholders’ average deposits decline below the outstanding credit balance. At the beginning of 2018, the Company changed the monitoring of such balances from quarterly to monthly. December 31, 2017 (in thousands) Brazil Venezuela Chile Others (1) Total Real estate loans Single-family residential (2) $ 219 $ 145,069 $ 179 $ 7,246 $ 152,713 Loans to financial institutions and acceptances 129,372 — 93,000 258,811 481,183 Commercial loans 8,451 — — 60,843 69,294 Consumer loans and overdrafts (3) 3,046 37,609 1,364 10,060 52,079 $ 141,088 $ 182,678 $ 94,543 $ 336,960 $ 755,269 __________________ (1) Loans to borrowers in eighteen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit secured to customers with deposits with the Bank. Charging privileges are suspended, if the deposits decline below the outstanding credit balance. The age analysis of the loan portfolio by class, including nonaccrual loans, as of December 31, 2018 and 2017 are summarized in the following tables: December 31, 2018 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,809,356 $ 1,809,356 $ — $ — $ — $ — $ — $ — Multi-family residential 909,439 909,439 — — — — — — Land development and construction loans 326,644 326,644 — — — — — — 3,045,439 3,045,439 — — — — — — Single-family residential 533,481 519,730 7,910 2,336 3,505 13,751 6,689 419 Owner-occupied 777,022 773,876 2,800 160 186 3,146 4,983 — 4,355,942 4,339,045 10,710 2,496 3,691 16,897 11,672 419 Commercial loans 1,380,428 1,378,022 704 1,062 640 2,406 4,772 — Loans to financial institutions and acceptances 68,965 68,965 — — — — — — Consumer loans and overdrafts 114,840 113,227 474 243 896 1,613 35 884 $ 5,920,175 $ 5,899,259 $ 11,888 $ 3,801 $ 5,227 $ 20,916 $ 16,479 $ 1,303 December 31, 2017 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,713,104 $ 1,712,624 $ — $ — $ 480 $ 480 $ 489 $ — Multi-family residential 839,709 839,709 — — — — — — Land development and construction loans 406,940 406,940 — — — — — — 2,959,753 2,959,273 — — 480 480 489 — Single-family residential 512,754 501,393 6,609 2,750 2,002 11,361 5,004 226 Owner-occupied 610,386 602,643 3,000 174 4,569 7,743 12,227 — 4,082,893 4,063,309 9,609 2,924 7,051 19,584 17,720 226 Commercial loans 1,354,755 1,350,667 385 5 3,698 4,088 8,947 — Loans to financial institutions and acceptances 497,626 497,626 — — — — — — Consumer loans and overdrafts 130,951 130,846 57 29 19 105 55 — $ 6,066,225 $ 6,042,448 $ 10,051 $ 2,958 $ 10,768 $ 23,777 $ 26,722 $ 226 At December 31, 2018 and 2017 , loans with an outstanding principal balance of $1,680 million and $1,476 million , respectively, were pledged as collateral to secure advances from the FHLB.

Allowance for Loan Losses

Allowance for Loan Losses	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Allowance for Loan Losses	Allowance for Loan Losses The analyses by loan segment of the changes in the allowance for loan losses for the three months ended March 31, 2019 and 2018 , and its allocation by impairment methodology and the related investment in loans, net as of March 31, 2019 and 2018 are summarized in the following tables: Three Months Ended March 31, 2019 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 22,778 $ 30,018 $ 445 $ 8,521 $ 61,762 (Reversal of) provision for loan losses (322 ) (31 ) (339 ) 692 — Loans charged-off Domestic — (992 ) — (196 ) (1,188 ) International — (18 ) — (406 ) (424 ) Recoveries — 123 — 49 172 Balances at end of the period $ 22,456 $ 29,100 $ 106 $ 8,660 $ 60,322 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 1,593 $ — $ 1,202 $ 2,795 Collectively evaluated 22,456 27,507 106 7,458 57,527 $ 22,456 $ 29,100 $ 106 $ 8,660 $ 60,322 Investment in loans, net of unearned income Individually evaluated $ 711 $ 12,325 $ — $ 3,392 $ 16,428 Collectively evaluated 3,016,569 2,137,165 27,985 536,291 5,718,010 $ 3,017,280 $ 2,149,490 $ 27,985 $ 539,683 $ 5,734,438 Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (821 ) 535 (691 ) 977 — Loans charged-off Domestic — (382 ) — (19 ) (401 ) International — — — (400 ) (400 ) Recoveries 34 832 — 53 919 Balances at end of the period $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,226 $ — $ — $ 2,226 Collectively evaluated 30,503 31,446 3,671 4,272 69,892 $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Investment in loans, net of unearned income Individually evaluated $ 11,238 $ 15,055 $ — $ 342 $ 26,635 Collectively evaluated 2,803,394 2,139,788 416,292 564,341 5,923,815 $ 2,814,632 $ 2,154,843 $ 416,292 $ 564,683 $ 5,950,450 The following is a summary of the recorded investment amount of loan sales by portfolio segment: Three Months Ended March 31, Real Estate Commercial Financial Consumer Total 2019 $ 23,475 $ 126,838 $ — $ 1,864 $ 152,177 2018 $ 2,958 $ 10,000 $ — $ — $ 12,958 The following is a summary of impaired loans as of March 31, 2019 and December 31, 2018 March 31, 2019 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average (1) Total Unpaid Principal Balance Valuation Allowance Real estate loans Commercial real estate Nonowner occupied $ — $ — $ — $ 5,188 $ — $ — Multi-family residential — 711 711 719 716 — Land development and construction — — — — — — — 711 711 5,907 716 — Single-family residential 3,411 289 3,700 4,182 3,802 1,346 Owner occupied 363 4,352 4,715 5,187 4,715 159 3,774 5,352 9,126 15,276 9,233 1,505 Commercial loans 7,169 120 7,289 7,178 8,427 1,289 Consumer loans and overdrafts 2 11 13 17 11 1 $ 10,945 $ 5,483 $ 16,428 $ 22,471 $ 17,671 $ 2,795 December 31, 2018 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average (1) Total Unpaid Principal Balance Valuation Allowance Real estate loans Commercial real estate Nonowner occupied $ — $ — $ — $ 7,935 $ — $ — Multi-family residential — 717 717 724 722 — Land development and construction loans — — — — — — — 717 717 8,659 722 — Single-family residential 3,086 306 3,392 4,046 3,427 1,235 Owner occupied 169 4,427 4,596 5,524 4,601 75 3,255 5,450 8,705 18,229 8,750 1,310 Commercial loans 4,585 148 4,733 7,464 6,009 1,059 Consumer loans and overdrafts 9 11 20 15 17 4 $ 7,849 $ 5,609 $ 13,458 $ 25,708 $ 14,776 $ 2,373 _______________ (1) Average using trailing four quarter balances. During the three months ended March 31, 2019 and 2018, the Company recognized interest income of $ 18 thousand and $25 thousand , respectively, on impaired loans. There were no new troubled debt restructurings (“TDRs”) during the three months ended March 31, 2019 . Consequently, during the three months ended March 31, 2019, the Company did not incur any charge-offs against the allowance for loan losses as a result of TDR loans. Since March 31, 2018, no TDRs subsequently defaulted under the modified terms of the loan agreement. Credit Risk Quality The Company’s investment in loans by credit quality indicators as of March 31, 2019 and December 31, 2018 are summarized in the following tables: March 31, 2019 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,844,618 $ 8,285 $ — $ — $ — $ 1,852,903 Multi-family residential 877,574 665 — — 878,239 Land development and construction loans 291,416 — — — — 291,416 3,013,608 8,285 665 — — 3,022,558 Single-family residential 528,792 — 6,514 — — 535,306 Owner occupied 780,457 12,767 8,632 — — 801,856 4,322,857 21,052 15,811 — — 4,359,720 Commercial loans 1,225,901 3,992 9,073 559 — 1,239,525 Loans to financial institutions and acceptances 27,985 — — — — 27,985 Consumer loans and overdrafts 101,264 — 5,944 — — 107,208 $ 5,678,007 $ 25,044 $ 30,828 $ 559 $ — $ 5,734,438 December 31, 2018 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,802,573 $ 6,561 $ 222 $ — $ — $ 1,809,356 Multi-family residential 909,439 — — — — 909,439 Land development and construction loans 326,644 — — — — 326,644 3,038,656 6,561 222 — — 3,045,439 Single-family residential 526,373 — 7,108 — — 533,481 Owner occupied 758,552 9,019 9,451 — — 777,022 4,323,581 15,580 16,781 — — 4,355,942 Commercial loans 1,369,434 3,943 6,462 589 — 1,380,428 Loans to financial institutions and acceptances 68,965 — — — — 68,965 Consumer loans and overdrafts 108,778 — 6,062 — — 114,840 $ 5,870,758 $ 19,523 $ 29,305 $ 589 $ — $ 5,920,175	Allowance for Loan Losses The analyses by loan segment of the changes in the allowance for loan losses for the years ended December 31, 2018 , 2017 and 2016 and its allocation by impairment methodology and the related investment in loans, net as of December 31, 2018 , 2017 and 2016 are summarized in the following tables: December 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the year $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (2,885 ) 1,099 (3,917 ) 6,078 375 Loans charged-off Domestic (5,839 ) (3,662 ) — (194 ) (9,695 ) International — (1,473 ) — (1,392 ) (2,865 ) Recoveries 212 1,367 — 368 1,947 Balances at end of the year $ 22,778 $ 30,018 $ 445 $ 8,521 $ 61,762 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 1,282 $ — $ 1,091 $ 2,373 Collectively evaluated 22,778 28,736 445 7,430 59,389 $ 22,778 $ 30,018 $ 445 $ 8,521 $ 61,762 Investment in loans, net of unearned income Individually evaluated $ 717 $ 9,652 $ — $ 3,089 $ 13,458 Collectively evaluated 3,037,604 2,254,607 69,003 545,503 5,906,717 $ 3,038,321 $ 2,264,259 $ 69,003 $ 548,592 $ 5,920,175 December 31, 2017 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the year $ 30,713 $ 40,897 $ 5,304 $ 4,837 $ 81,751 Reversal of provision for loan losses (221 ) (1,027 ) (942 ) (1,300 ) (3,490 ) Loans charged-off Domestic (97 ) (1,979 ) — (424 ) (2,500 ) International — (6,166 ) — (757 ) (6,923 ) Recoveries 895 962 — 1,305 3,162 Balances at end of the year $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,866 $ — $ — $ 2,866 Collectively evaluated 31,290 29,821 4,362 3,661 69,134 $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 Investment in loans, net of unearned income Individually evaluated $ 1,318 $ 20,907 $ — $ 374 $ 22,599 Collectively evaluated 2,912,786 2,073,351 497,626 559,863 6,043,626 $ 2,914,104 $ 2,094,258 $ 497,626 $ 560,237 $ 6,066,225 December 31, 2016 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the year $ 18,331 $ 44,734 $ 9,226 $ 4,752 $ 77,043 Provision for (reversal of) loan losses 8,570 16,153 (3,922 ) 1,309 22,110 Loans charged-off Domestic (94 ) (1,496 ) — (224 ) (1,814 ) International — (19,610 ) — (1,186 ) (20,796 ) Recoveries 3,906 1,116 — 186 5,208 Balances at end of the year $ 30,713 $ 40,897 $ 5,304 $ 4,837 $ 81,751 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 6,596 $ — $ — $ 6,596 Collectively evaluated 30,713 34,301 5,304 4,837 75,155 $ 30,713 $ 40,897 $ 5,304 $ 4,837 $ 81,751 Investment in loans, net of unearned income Individually evaluated $ 13,792 $ 51,332 $ — $ 4,205 $ 69,329 Collectively evaluated 2,364,161 2,398,552 416,336 516,383 5,695,432 $ 2,377,953 $ 2,449,884 $ 416,336 $ 520,588 $ 5,764,761 The following is a summary of the recorded investment amount of loan sales by portfolio segment in the years ended December 2018, 2017 and 2016: (in thousands) Real Estate Commercial Financial Consumer Total 2018 $ 20,248 $ 138,244 $ — $ 14,981 $ 173,473 2017 $ 15,040 $ 35,260 $ 40,177 $ — $ 90,477 2016 $ 9,151 $ 72,597 $ 23,500 $ — $ 105,248 The following is a summary of impaired loans as of December 31, 2018 and 2017 : December 31, 2018 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average Total Unpaid Principal Balance Valuation Allowance Interest Income Recognized Real estate loans Commercial real estate Nonowner occupied $ — $ — $ — $ 7,935 $ — $ — — Multi-family residential — 717 717 724 722 — 32 Land development and construction — — — — — — — — 717 717 8,659 722 — 32 Single-family residential 3,086 306 3,392 4,046 3,427 1,235 108 Owner-occupied 169 4,427 4,596 5,524 4,601 75 14 3,255 5,450 8,705 18,229 8,750 1,310 154 Commercial loans 4,585 148 4,733 7,464 6,009 1,059 952 Consumer loans and overdrafts 9 11 20 15 17 4 — $ 7,849 $ 5,609 $ 13,458 $ 25,708 $ 14,776 $ 2,373 $ 1,106 December 31, 2017 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average Total Unpaid Principal Balance Valuation Allowance Interest Income Recognized Real estate loans Commercial real estate Nonowner occupied $ — $ 327 $ 327 $ 225 $ 327 $ — $ — Multi-family residential — 1,318 1,318 7,898 1,330 — 54 Land development and construction loans — — — 1,359 — — — — 1,645 1,645 9,482 1,657 — 54 Single-family residential — 877 877 3,100 871 — 1,101 Owner-occupied — 10,918 10,918 13,440 12,323 — 11 — 13,440 13,440 26,022 14,851 — 1,166 Commercial loans 7,173 1,986 9,159 18,211 14,784 2,866 12 Consumer loans and overdrafts — — — — — — — $ 7,173 $ 15,426 $ 22,599 $ 44,233 $ 29,635 $ 2,866 $ 1,178 Troubled Debt Restructurings The following table shows information about loans that were modified and met the definition of TDR during 2018, 2017 and 2016: 2018 2017 2016 (in thousands) Number of Contracts Recorded Investment Number of Contracts Recorded Investment Number of Contracts Recorded Investment Real estate loans Commercial real estate Nonowner occupied (1) 1 $ — — $ — 1 $ 208 Single-family residential — — 2 — 1 49 Owner-occupied 1 1,831 1 — 3 846 2 1,831 3 — 5 1,103 Commercial loans 2 622 1 1,473 2 11,172 Consumer loans and overdrafts 1 10 — — — — Total (2) (3) 5 $ 2,463 4 $ 1,473 7 $ 12,275 _________________ (1) In the fourth quarter of 2018, the Company sold one non-performing loan in the Houston area with a carrying value of $10.2 million , and charged off $5.8 million against the allowance for loan losses. This loan had been modified and met the definition of a TDR during the second quarter of 2018. (2) During 2018 and 2017, the Company charged off a total of approximately $6.9 million and $6.0 million , respectively, against the allowance for loan losses as a result of these TDR loans. (3) At December 31, 2018, 2017 and 2016, all TDR loans were primarily real estate and commercial loans under modified terms, including interest payment deferments and others, that did not substantially impact the allowance for loan losses since the recorded investment in these impaired loans corresponded to their realizable value, which approximated their fair values, or higher, prior to their designation as TDR. During 2018, 2017 and 2016, TDR loans that subsequently defaulted within the 12 months of restructuring were as follows: 2018 2017 2016 (in thousands) Number of Contracts Recorded Investment Number of Contracts Recorded Investment Number of Contracts Recorded Investment Real estate loans Single-family residential — $ — — $ — 6 $ 3,010 Owner-occupied 1 1,831 1 618 4 2,959 1 1,831 1 618 10 5,969 Commercial loans 1 589 — — — — Consumer loans and overdrafts 1 10 — — — — 3 $ 2,430 1 $ 618 10 $ 5,969 Credit Risk Quality The sufficiency of the allowance for loan losses is reviewed monthly by the Chief Risk Officer and the Chief Financial Officer. These recommendations are reviewed and approved monthly by the Executive Management Committee. The Board of Directors considers the allowance for loan losses as part of its review of the Company’s consolidated financial statements. As of December 31, 2018 and 2017, the Company believes the allowance for loan losses to be sufficient to absorb losses in the loans portfolio in accordance with U.S. GAAP. Loans may be classified but not considered impaired due to one of the following reasons: (1) the Company has established minimum dollar amount thresholds for loan impairment testing, which results in loans under those thresholds being excluded from impairment testing and therefore not included in impaired loans; (2) classified loans may be considered nonimpaired because collection of all amounts due is probable. As part of the on-going monitoring of the credit quality of the Company’s loan portfolio, management tracks certain credit quality indicators including trends related primarily to (i) the risk rating of loans, (ii) the loan payment status, (iii) net charge-offs, (iv) nonperforming loans and (v) the general economic conditions in the main geographies where the Company’s borrowers conduct their businesses. The Company considers the views of its regulators as to loan classification and impairment. The Company utilizes a credit risk rating system to identify the risk characteristics of each of its loans, or group of homogeneous loans such as consumer loans. Loans are rated on a quarterly basis (or more frequently when the circumstances require it) on a scale from 1 (worst credit quality) to 10 (best credit quality). Loans are then grouped in five master risk categories for purposes of monitoring rising levels of potential loss risks and to enable the activation of collection or recovery processes as defined in the Company’s Credit Risk Policy. The following is a summary of the master risk categories and their associated loan risk ratings, as well as a description of the general characteristics of the master risk category: Loan Risk Rating Master risk category Nonclassified 4 to 10 Classified 1 to 3 Substandard 3 Doubtful 2 Loss 1 N onclassified This category includes loans considered as Pass and Special Mention. A loan classified as pass is considered of sufficient quality to preclude a lower adverse rating. These loans are generally well protected by the current net worth and paying capacity of the borrower or by the value of any collateral received. Special Mention loans are defined as having potential weaknesses that deserve management’s close attention which, if left uncorrected, could potentially result in further credit deterioration. Special Mention loans may include loans originated with certain credit weaknesses or that developed those weaknesses since their origination. Classified This classification indicates the presence of credit weaknesses which could make loan repayment unlikely, such as partial or total late payments and other contractual defaults. Substandard A loan classified substandard is inadequately protected by the sound worth and paying capacity of the borrower or the collateral pledged. They are characterized by the distinct possibility that the Company will sustain some loss if the credit weaknesses are not corrected. Loss potential, while existing in the aggregate amount of substandard loans, does not have to exist in individual assets. Doubtful These loans have all the weaknesses inherent in a loan classified as substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable. These are poor quality loans in which neither the collateral, if any, nor the financial condition of the borrower presently ensure collection in full in a reasonable period of time. As a result, the possibility of loss is extremely high. Loss Loans classified as loss are considered uncollectible and of such little value that the continuance as bankable assets is not warranted. This classification does not mean that the assets have absolutely no recovery or salvage value, but not to the point where a write-off should be deferred even though partial recoveries may occur in the future. This classification is based upon current facts, not probabilities. As a result, loans in this category should be promptly charged off in the period in which they surface as uncollectible. Loans by Credit Quality Indicators The Company’s loans by credit quality indicators as of December 31, 2018 and 2017 are summarized in the following tables: December 31, 2018 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,802,573 $ 6,561 $ 222 $ — $ — $ 1,809,356 Multi-family residential 909,439 — — — — 909,439 Land development and construction loans 326,644 — — — — 326,644 3,038,656 6,561 222 — — 3,045,439 Single-family residential 526,373 — 7,108 — — 533,481 Owner-occupied 758,552 9,019 9,451 — — 777,022 4,323,581 15,580 16,781 — — 4,355,942 Commercial loans 1,369,434 3,943 6,462 589 — 1,380,428 Loans to financial institutions and acceptances 68,965 — — — — 68,965 Consumer loans and overdrafts 108,778 — 6,062 — — 114,840 $ 5,870,758 $ 19,523 $ 29,305 $ 589 $ — $ 5,920,175 December 31, 2017 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,711,595 $ 1,020 $ 489 $ — $ — $ 1,713,104 Multi-family residential 839,709 — — — — 839,709 Land development and construction loans 406,940 — — — — 406,940 2,958,244 1,020 489 — — 2,959,753 Single-family residential 506,885 — 5,869 — — 512,754 Owner-occupied 592,468 4,051 13,867 — — 610,386 4,057,597 5,071 20,225 — — 4,082,893 Commercial loans 1,334,543 6,100 14,112 — — 1,354,755 Loans to financial institutions and acceptances 497,626 — — — — 497,626 Consumer loans and overdrafts 126,838 — 4,113 — — 130,951 $ 6,016,604 $ 11,171 $ 38,450 $ — $ — $ 6,066,225 Credit Risk Quality Indicators - Consumer Loan Classes The credit risk quality of the Company’s residential real estate and consumer loan portfolios is evaluated by considering the repayment performance of individual borrowers, and then classified on an aggregate or pool basis. Loan secured by real estate in these classes which have been past due 90 days or more, and 120 days (non-real estate secured) or 180 days or more, are classified as Substandard and Loss, respectively. When the Company has documented that past due loans in these classes are well-secured and in the process of collection, then the loans may not be classified. These indicators are updated at least quarterly. Single-family residential loans: December 31, (in thousands, except percentages) 2018 2017 2016 Loan Balance % Loan Balance % Loan Balance % Accrual Loans Current $ 518,106 97.12 % $ 499,307 97.38 % $ 455,410 96.80 % 30-59 Days Past Due 7,634 1.43 % 6,025 1.17 % 4,675 0.99 % 60-89 Days Past Due 633 0.12 % 2,193 0.43 % 1,395 0.30 % 90+ Days Past Due 419 0.08 % 225 0.04 % 116 0.02 % 8,686 1.63 % 8,443 1.64 % 6,186 1.31 % Total Accrual Loans $ 526,792 98.75 % $ 507,750 99.02 % $ 461,596 98.11 % Non-Accrual Loans Current $ 1,624 0.30 % $ 2,086 0.41 % $ 2,290 0.49 % 30-59 Days Past Due 276 0.05 % 584 0.11 % — — % 60-89 Days Past Due 1,703 0.32 % 557 0.11 % 38 0.01 % 90+ Days Past Due 3,086 0.58 % 1,777 0.35 % 6,565 1.39 % 5,065 0.95 % 2,918 0.57 % 6,603 1.40 % Total Non-Accrual Loans 6,689 1.25 % 5,004 0.98 % 8,893 1.89 % $ 533,481 100.00 % $ 512,754 100.00 % $ 470,489 100.00 % Consumer loans and overdrafts: December 31, (in thousands, except percentages) 2018 2017 2016 Loan Balance % Loan Balance % Loan Balance % Accrual Loans Current $ 113,211 98.58 % $ 130,830 99.91 % $ 120,463 98.40 % 30-59 Days Past Due 466 0.41 % 48 0.04 % 1,076 0.88 % 60-89 Days Past Due 243 0.21 % 18 0.01 % 443 0.36 % 90+ Days Past Due 885 0.77 % — — % 370 0.30 % 1,594 1.39 % 66 0.05 % 1,889 1.54 % Total Accrual Loans $ 114,805 99.97 % $ 130,896 99.96 % $ 122,352 99.94 % Non-Accrual Loans Current $ 16 0.01 % $ 16 0.01 % $ 43 0.03 % 30-59 Days Past Due 8 0.01 % 9 0.01 % 22 0.02 % 60-89 Days Past Due — — % 11 0.01 % — — % 90+ Days Past Due 11 0.01 % 19 0.01 % 9 0.01 % 19 0.02 % 39 0.03 % 31 0.03 % Total Non-Accrual Loans 35 0.03 % 55 0.04 % 74 0.06 % $ 114,840 100.00 % $ 130,951 100.00 % $ 122,426 100.00 %

Premises and Equipment, Net

Premises and Equipment, Net	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Premises and Equipment, Net	Premises and Equipment, Net Premises and equipment, net include the following: December 31, Estimated (in thousands) 2018 2017 (in years) Land $ 18,307 $ 18,307 NA Buildings and improvements 100,152 93,848 10–30 Equipment leased under an operating lease — 19,626 15 Furniture and equipment 21,579 19,832 3–10 Computer equipment and software 31,225 29,749 3 Leasehold improvements 19,301 18,260 5–10 Work in progress 5,170 6,532 NA $ 195,734 $ 206,154 Less: Accumulated depreciation and amortization (72,231 ) (76,797 ) $ 123,503 $ 129,357 There were no significant sales of properties in 2018. In 2017, the Company sold one property in New York City (the “New York Building”) and a Florida banking center building with a total carrying value of approximately $19.1 million and realized an aggregate gain on sale of approximately $11.3 million . In 2016, the Company sold properties with a carrying value of approximately $1.0 million and realized an aggregate gain on sale of approximately $2.0 million . In 2018, the Company sold all of its interest in an operating subsidiary, which held an aircraft leased solely to MSF under an operating lease. Depreciation and amortization expense was approximately $8.5 million , $9.0 million and $9.1 million in the years ended December 31, 2018, 2017 and 2016, respectively. In 2018, 2017 and 2016 fully-depreciated equipment with an original cost of approximately $0.8 million , $1.4 million and $1.9 million , respectively, were written-off and charged against their respective accumulated depreciation.

Time Deposits

Time Deposits	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Banking and Thrift [Abstract]
Time Deposits	Time Deposits Time deposits in denominations of $100,000 or more amounted to approximately $1.4 billion at March 31, 2019 and December 31, 2018 . Time deposits in denominations of $250,000 or more amounted to approximately $739 million and $718 million at March 31, 2019 and December 31, 2018 , respectively. Time deposits include brokered time deposits, all in denominations of less than $100,000 . As of March 31, 2019 and December 31, 2018 , brokered time deposits amounted to $589 million and $642 million , respectively.	Time Deposits Time deposits in denominations of $100,000 or more amounted to approximately $1.4 billion and $1.2 billion at December 31, 2018 and 2017 , respectively. Time deposits in denominations of $250,000 or more amounted to approximately $718 million and $624 million at December 31, 2018 and 2017 , respectively. The average interest rate paid on time deposits was approximately 2.51% in 2018 and 1.26% in 2017 . Time deposits include brokered time deposits, all in denominations of less than $100,000 . As of December 31, 2018 and 2017 brokered time deposits amounted to $642 million and $780 million , respectively. At December 31, 2018 and 2017 time deposits maturities were as follows: (in thousands, except percentages) 2018 2017 Year of Maturity Amount % Amount % 2018 $ — — % $ 1,357,668 60.44 % 2019 1,438,565 60.26 % 331,515 14.76 % 2020 361,255 15.13 % 194,175 8.64 % 2021 168,850 7.07 % 103,781 4.62 % 2022 135,265 5.67 % 106,550 4.74 % 2023 and thereafter 283,196 11.87 % 152,745 6.80 % Total $ 2,387,131 100.00 % $ 2,246,434 100.00 %

Advances From the Federal Home

Advances From the Federal Home Loan Bank and Other Borrowings	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Banking and Thrift [Abstract]
Advances From the Federal Home Loan Bank and Other Borrowings	Advances From the Federal Home Loan Bank and Other Borrowings The Company had outstanding advances from the FHLB and other borrowings. These borrowings bear fixed interest rates or variable rates based on 3-month LIBOR as follows: Year of Maturity Interest March 31, 2019 December 31, 2018 (in thousands, except percentages) 2019 1.80% to 3.86% $ 385,000 $ 440,000 2020 1.50% to 2.74% 265,000 306,000 2021 1.93% to 3.08% 210,000 210,000 2022 2.48% to 2.80% 120,000 120,000 2023 and after 2.95% to 3.23% 90,000 90,000 $ 1,070,000 $ 1,166,000	Advances From the Federal Home Loan Bank and Other Borrowings At December 31, 2018 and 2017, the Company had outstanding advances from the FHLB and other borrowings as follows: Year of Maturity Interest December 31, 2018 December 31, 2017 (in thousands, except percentages) 2018 0.90% to 2.03% $ — $ 567,000 2019 1.00% to 3.86% 440,000 155,000 2020 1.50% to 2.74% 306,000 211,000 2021 1.93% to 3.08% 210,000 240,000 2022 and after 2.48% to 3.23% 210,000 — $ 1,166,000 $ 1,173,000 At December 31, 2018, advances from the FHLB include $280 million ( $255 million in 2017) which have variable interest rates ranging from 2.40% to 2.82% with maturities in 2019 ( 1.23% to 1.71% with maturities in 2018 and 2019). At December 31, 2018 and 2017, the Company held stock of the FHLB for approximately $57 million . The terms of the Company’s advance agreement with the FHLB require the Company to maintain certain investment securities and loans as collateral for these advances. At December 31, 2018 and 2017, the Company was in compliance with this requirement. There were no other borrowings at December 31, 2018. Other borrowings at December 31, 2017 included $12 million in advances from other banks which matured in January 2018.

Derivative Instruments

Derivative Instruments	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments At March 31, 2019 and December 31, 2018 , the fair values of the Company’s derivative instruments were as follows: March 31, 2019 December 31, 2018 (in thousands) Other Assets Other Liabilities Other Assets Other Liabilities Interest rate swaps designated as cash flow hedges $ — $ — $ 9,386 $ 283 Interest rate swaps not designated as hedging instruments: Customers 4,815 — 1,420 — Third party broker — 4,815 — 1,420 4,815 4,815 1,420 1,420 Interest rate caps not designated as hedging instruments: Customers — 176 — 685 Third party broker 176 — 685 — 176 176 685 685 $ 4,991 $ 4,991 $ 11,491 $ 2,388 Derivatives Designated as Hedging Instruments In February and March 2019, the Company terminated the interest rate swaps designated as cash flow hedges. The Company will recognize the contracts’ cumulative net unrealized gains in earnings over the remaining original life of the terminated interest rate swaps. At December 31, 2018 , the Company’s interest rate swaps designated as cash flow hedges involved the Company’s payment of fixed-rate amounts in exchange for the Company receiving variable-rate payments over the life of the agreements without exchange of the underlying notional amount. At December 31, 2018 , the Company had 16 interest rate swap contracts with total notional amounts of $280 million , that were designated as cash flow hedges of floating rate interest payments on the outstanding and expected rollover of variable-rate advances from the FHLB. These hedge relationships were expected to be highly effective in offsetting the effects of changes in interest rates in the cash flows associated with the advances from the FHLB. No hedge ineffectiveness gains or losses were recognized in the three months ended March 31, 2019 and 2018 . Derivatives Not Designated as Hedging Instruments At March 31, 2019 and December 31, 2018 , the Company had twelve and eight interest rate swap contracts with customers with a total notional amount of $145.4 million and $80.4 million , respectively. These instruments involve the payment of fixed-rate amounts in exchange for the Company receiving variable-rate payments over the life of the contract. In addition, at March 31, 2019 and December 31, 2018 , the Company had interest rate swap mirror contracts with a third party broker with similar terms. At March 31, 2019 and December 31, 2018 , the Company had sixteen interest rate cap contracts with customers with a total notional amount of $320.8 million and $323.7 million , respectively. In addition, at March 31, 2019 and December 31, 2018 , the Company had interest rate cap mirror contracts with various third party brokers with similar terms.	Derivative Instruments From time to time, the Company enters into derivative financial instruments as part of its interest rate management activities and to facilitate customer transactions. Those instruments may or not be designated and qualify as part of a hedging relationship. The customer derivatives we use for the Company’s account are matched against derivatives from third parties, but are not designated as hedging instruments. At December 31, 2018 and 2017 the fair value of the Company’s derivative instruments was as follows: December 31, 2018 December 31, 2017 (in thousands) Other Assets Other Liabilities Other Assets Other Liabilities Interest rate swaps designated as cash flow hedges $ 9,386 $ 283 $ 5,462 $ — Interest rate swaps not designated as hedging instruments: Customers 1,420 — 1,375 — Third party broker — 1,420 — 1,375 1,420 1,420 1,375 1,375 Interest rate caps not designated as hedging instruments: Customers — 685 — 195 Third party broker 685 — 195 — 685 685 195 195 $ 11,491 $ 2,388 $ 7,032 $ 1,570 Derivatives Designated as Hedging Instruments The Company maintains interest rate swaps contracts which the Company had designated and qualified as cash flow hedges. These interest rate swaps were designed as cash flow hedges to manage the exposure that arises from differences in the amount of the Company’s known or expected cash receipts and the known or expected cash payments related to the Company’s variable-rate borrowings from the FHLB, the value of which are determined by interest rates. At December 31, 2018 and 2017 the Company’s interest rate swaps designated as cash flow hedges involve the Company’s payment of fixed-rate amounts in exchange for the Company receiving variable-rate payments over the life of the agreements without exchange of the underlying notional amount. At December 31, 2018 and 2017 , respectively, the Company had 16 and 15 interest rate swap contracts with total notional amounts of $280 million and $255 million , respectively, that were designated as cash flow hedges of floating rate interest payments on the currently outstanding and expected rollover of variable-rate advances from the FHLB. At December 31, 2018, these advances have a carrying amount of $280 million and maturities of less than one year ( $366 million with maturities ranging from two to nine years at December 31, 2017). The interest rate swaps mature in one to eight years ( three to nine years in 2017). The Company expects the hedge relationships to be highly effective in offsetting the effects of changes in interest rates in the cash flows associated with the advances from the FHLB. No hedge ineffectiveness gains or losses were recognized in the years ended December 31, 2018 and 2017 . In February and March 2019, the Company terminated the interest rate swaps designated as cash flow hedges. The Company will recognize the contracts cumulative net unrealized gains in earnings over the remaining original life of the terminated interest rate swaps. Derivatives Not Designated as Hedging Instruments At December 31, 2018 and 2017 , the Company had eight and one interest rate swap contracts with customers with a total notional amount of $80.4 million and $54.6 million , respectively. These instruments involve the payment of fixed-rate amounts in exchange for the Company receiving variable-rate payments over the life of the contracts. In addition, at December 31, 2018 and 2017 , the Company had interest rate swap mirror contracts with a third party broker with similar terms. These instruments have maturities ranging from 5 to 10 years ( 10 years in 2017) and do not involve the exchange of the underlying notional amount. At December 31, 2018 and 2017 , the Company had sixteen and seven interest rate cap contracts with customers with a total notional amount of $323.7 million and $162.1 million , respectively. In addition, at December 31, 2018 and 2017 , the Company had interest rate cap mirror contracts with various third party brokers with similar terms. These instruments’ maturities range from less than 1 to 5 years (1 and half years to 4 years in 2017).

Junior Subordinated Debentures

Junior Subordinated Debentures Held by Trust Subsidiaries	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Junior Subordinated Debentures Held by Trust Subsidiaries	Junior Subordinated Debentures Held by Trust Subsidiaries At December 31, 2018 and 2017, the Company owns all of the common capital securities issued by 8 statutory trust subsidiaries (“the Trust Subsidiaries”). These Trust Subsidiaries were first formed by the Company for the purpose of issuing trust preferred securities (“the Trust Preferred Securities”) and investing the proceeds in junior subordinated debentures issued by the Company. The debentures are guaranteed by the Company. The Company records the common capital securities issued by the Trust Subsidiaries in other assets in its consolidated balance sheets using the equity method. The junior subordinated debentures issued to the Trust Subsidiaries, less the common securities of the Trust Subsidiaries, qualify as Tier 1 regulatory capital. The following table provides information of the outstanding Trust Preferred Securities issued by, and the junior subordinated debentures issued to, each of the Trust Subsidiaries as of December 31, 2018 and 2017: (in thousands) Amount of Principal Year of Annual Rate of Trust Year of Commercebank Capital Trust I $ 26,830 $ 28,068 1998 8.90% 2028 Commercebank Statutory Trust II 15,000 15,464 2000 10.60% 2030 Commercebank Capital Trust III 10,000 10,400 2001 10.18% 2031 Commercebank Capital Trust VI 9,250 9,537 2002 3-M LIBOR + 3.35% 2033 Commercebank Capital Trust VII 8,000 8,248 2003 3-M LIBOR + 3.25% 2033 Commercebank Capital Trust VIII 5,000 5,155 2004 3-M LIBOR + 2.85% 2034 Commercebank Capital Trust IX 25,000 25,774 2006 3-M LIBOR + 1.75% 2038 Commercebank Capital Trust X 15,000 15,464 2006 3-M LIBOR + 1.78% 2036 $ 114,080 $ 118,110 The Company and the Trust Subsidiaries have the option to defer payment of interest on the obligations for up to 10 semi-annual periods. In 2018 and 2017, no payment of interest have been deferred on these obligations. The Trust Preferred Securities are subject to mandatory redemption, in whole or in part, upon the maturity or early redemption of the debentures. Early redemption premiums may be payable.

Incentive Compensation and Bene

Incentive Compensation and Benefit Plans	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Incentive Compensation and Benefit Plans	Stock-based Incentive Compensation Plan The Company sponsors the Mercantil Bank Holding Corporation 2018 Equity and Incentive Compensation Plan (the “2018 Equity Plan”). See Note 11 to the Company’s audited consolidated financial statements on the Form 10-K for more information on the 2018 Equity Plan and restricted stock awards for the year ended 2018. On January 21, 2019, the Company granted 1,299 shares of restricted stock to one of its employees. These shares of restricted stock will vest in three approximately equal amounts on each of January 21, 2020, 2021 and 2022. The fair value of the restricted stock granted was based on the market price of the shares of the Company’s Class A common stock at the grant date which was $13.50 . During the three months ended March 31, 2019, the Company recorded $1.5 million of compensation expense related to restricted stock awards granted in December 2018 and January 2019. The total unamortized deferred compensation expense of $8.3 million for all unvested restricted stock outstanding at March 31, 2019 will be recognized over a weighted average period of 2 years .	Incentive Compensation and Benefit Plans a) Stock-based Incentive Compensation Plan On March 12, 2018, MSF, our sole shareholder at that time, approved the Mercantil Bank Holding Corporation 2018 Equity and Incentive Compensation Plan (the “2018 Equity Plan”). The Company has reserved up to 3,333,333 shares of Class A common stock for issuance pursuant the grant of options rights, appreciation rights, restricted stock, restricted stock units and other awards under the 2018 Equity Plan. On December 21, 2018, in connection with the closing of the Company’s IPO, the Company’s directors were granted restricted stock units, and various Company officers and employees were granted restricted Class A common stock awards, under the 2018 Equity Plan. Restricted Stock Awards On December 21, 2018, the Company granted 736,839 shares of restricted Class A common stock to officers and employees. These shares of restricted stock will vest in three approximately equal amounts on each of December 21, 2019, 2020 and 2021. The fair value of the restricted stock granted was based on the market price of the shares of the Company’s Class A common stock at the grant date which was $13.45 . In 2018, the Company recorded $0.2 million of compensation expense related to these restricted stock awards. The total unearned deferred compensation expense of $9.8 million for all unvested restricted stock outstanding at December 31, 2018 will be recognized over a weighted average period of 2 years . Restricted Stock Units On December 21, 2018, the Company granted 86,535 restricted stock units (“RSUs”) to its non-employee directors. Of the 86,535 RSUs, 57,690 RSUs are settled in shares of Class A common stock while the remaining 28,845 RSUs are settled in cash, both upon vesting. These RSUs will vest in three approximately equal amounts on each of December 21, 2019, 2020 and 2021. b) Employee Benefit Plan The Mercantil Bank U.S.A. Retirement Plan (the “401(k) Plan”) is a 401(k) benefit plan covering substantially all employees of the Company. The Company matches 100% of each participant’s contribution up to a maximum of 5% of their annual salary. Contributions by the Company to the Plan are based upon a fixed percentage of participants’ salaries as defined by the Plan. The Plan enables Highly Compensated employees to contribute up to the maximum allowed without further restrictions. All contributions made by the Company to the participants’ accounts are vested immediately. In addition, employees with at least three months of service and who have reached the age of 21 may contribute a percentage of their salaries to the Plan as elected by each participant. The Company contributed to the Plan approximately $5 million and $4 million in 2018 and 2017, respectively, in matching contributions. The Company maintains the Amerant Bank, N.A. Executive Deferred Compensation Plan as a non-qualified plan for eligible highly compensated employees (the “Deferred Compensation Plan”). The Deferred Compensation Plan permits deferrals of compensation above the amounts that can be contributed for retirement under the 401(k) Plan. Under the Deferred Compensation Plan, eligible employees may elect to defer a portion of their annual salary and cash incentive awards and allows them to receive matching contributions up to 5% of their annual salary. All deferrals, employer contributions, earnings, and gains on each participant’s account in the Deferred Compensation Plan are vested immediately. The Spin-off caused an unexpected early distribution for U.S. federal income tax purposes from the Deferred Compensation Plan. The Company partially compensated plan participants, in the aggregate amount of $1.2 million , for the higher tax expense they will incur as a result of the distribution increasing the plan participants’ estimated effective federal income tax rates by recording a contribution to the plan on behalf of its participants.

Income Taxes

Income Taxes	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company uses an estimated annual effective tax rate method in computing its interim tax provision. This effective tax rate is based on forecast annual consolidated pre-tax income, permanent tax differences and statutory tax rates. Under this method, the tax effect of certain items that do not meet the definition of ordinary income or expense are computed and recognized as discrete items when they occur. The effective combined federal and state tax rates for the three months ended March 31, 2019 and 2018 were 21.49% and 13.76% , respectively. Effective tax rates differ from the statutory rates mainly due to the impact of forecast permanent non-taxable interest and other income, and the impact of permanent non-deductible discrete expense items incurred during the period, which primarily include the non-deductible spin-off costs in 2018 and the effect of corporate state taxes.	Income Taxes The components of the income tax expense for the years ended December 31, 2018, 2017 and 2016 are as follows: (in thousands) 2018 2017 2016 Current provision Federal $ 7,298 $ 19,194 $ 10,981 State 1,964 1,763 844 Impact of lower rate under the 2017 Tax Act - Remeasurement of net deferred tax assets, other than balances corresponding to items in AOCI — 8,470 — Remeasurement of net deferred tax assets corresponding to items in AOCI — 1,094 — Deferred tax expense (benefit) 2,471 3,471 (1,614 ) $ 11,733 $ 33,992 $ 10,211 On December 22, 2017, the 2017 Tax Act was signed into law. This law significantly changes U.S. tax law by, among other things, lowering corporate federal income tax rates and implementing a territorial tax system. The legislation permanently reduces the U.S. corporate income tax rate from 35% to 21%, effective January 1, 2018. As a result of the reduction in the U.S. corporate federal income tax rate, the Company remeasured its ending net deferred tax assets at December 31, 2017 and recognized a total of $9.6 million tax expense in the Company’s consolidated statement of income for the year ended December 31, 2017. A reconciliation of the income tax expense at the statutory federal income tax rate to the Company’s effective income tax rate for the years ended December 31, 2018, 2017, and 2016 follows: 2018 2017 2016 (in thousands) Amount % Amount % Amount % Tax expense calculated at the statutory federal income tax rate $ 12,089 21.00 % $ 26,967 35.00 % $ 11,827 35.00 % Increases (decreases) resulting from: Impact of the 2017 Tax Act - Remeasurement of net deferred tax assets — — % 9,564 12.41 % — — % Non-taxable interest income (1,507 ) (2.62 )% (1,643 ) (2.13 )% (1,132 ) (3.35 )% Non-taxable BOLI income (1,223 ) (2.12 )% (1,910 ) (2.48 )% (1,547 ) (4.58 )% Non-deductible Spin-off costs 1,711 2.97 % — — % — — % Disallowed interest expense allocable to tax exempt securities and other expenses 627 1.09 % 577 0.75 % 464 1.37 % State and city income taxes, net of federal income tax benefit (131 ) (0.23 )% 1,146 1.49 % 549 1.62 % Other, net 167 0.29 % (709 ) (0.92 )% 50 0.16 % $ 11,733 20.38 % $ 33,992 44.12 % $ 10,211 30.22 % The composition of the net deferred tax asset is as follows: December 31, (in thousands) 2018 2017 Tax effect of temporary differences Provision for loan losses $ 13,581 $ 13,372 Net unrealized losses in other comprehensive income 5,878 1,680 Deferred compensation expense 3,489 3,460 Dividend income 605 946 Interest income on nonaccrual loans 341 599 Goodwill amortization (3,979 ) (3,223 ) Depreciation and amortization (3,934 ) (3,601 ) Other 329 1,350 Net deferred tax assets $ 16,310 $ 14,583 The Company evaluates the deferred tax asset for recoverability using a consistent approach which considers the relative impact of negative and positive evidence, including its own historical financial performance and that of its operating subsidiaries and projections of future taxable income. This evaluation involves significant judgment by management about assumptions that are subject to change from period to period. Management believes that the weight of all the positive evidence currently available exceeds the negative evidence in support of the realization of the future tax benefits associated with the federal net deferred tax asset. As a result, management has concluded that the federal net deferred tax asset in its entirety will more likely than not be realized. Therefore, a valuation allowance is not considered necessary. If future results differ significantly from the Company’s current projections, a valuation allowance against the net deferred tax asset may be required. At December 31, 2018 and 2017, the Company had accumulated net operating losses (“NOLs”) in the State of Florida of approximately $151.9 million and $143.6 million , respectively. These NOLs are carried forward for a maximum of 20 years based on applicable Florida law. The deferred tax asset related to these NOLs at December 31, 2018 and 2017 is approximately $6.6 million and $6.2 million , respectively. A full valuation allowance has been recorded against the state deferred tax asset related to these NOLs as management believes it is more likely than not that the tax benefit will not be realized. At December 31, 2018 and 2017, the Company had no unrecognized tax benefits or associated interest or penalties that needed to be accrued.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss (“AOCL”)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Accumulated Other Comprehensive Loss (“AOCL”)	Accumulated Other Comprehensive Loss (“AOCL”): The components of AOCL are summarized as follows using applicable blended average federal and state tax rates for each period: March 31, 2019 December 31, 2018 (in thousands) Before Tax Tax Net of Tax Before Tax Tax Net of Tax Unrealized losses on available for sale securities $ (11,604 ) $ 2,838 $ (8,766 ) $ (33,145 ) $ 8,104 $ (25,041 ) Unrealized gains on interest rate swaps designated as cash flow hedges 8,759 (2,142 ) $ 6,617 9,103 (2,226 ) $ 6,877 Total AOCL $ (2,845 ) $ 696 $ (2,149 ) $ (24,042 ) $ 5,878 $ (18,164 ) The components of other comprehensive income (loss) for the periods presented are summarized as follows: Three Months Ended March 31, 2019 2018 (in thousands) Before Tax Tax Net of Tax Before Tax Tax Net of Tax Unrealized gains (losses) on available for sale securities: Change in fair value arising during the period $ 21,545 $ (5,267 ) $ 16,278 $ (20,850 ) $ 5,873 $ (14,977 ) Reclassification adjustment for net gains included in net income (4 ) 1 (3 ) — — — 21,541 (5,266 ) 16,275 (20,850 ) 5,873 (14,977 ) Unrealized (losses) gains on interest rate swaps designated as cash flow hedges: Change in fair value arising during the period (15 ) 4 (11 ) 6,101 (1,821 ) 4,280 Reclassification adjustment for net interest (income) expense included in net income (329 ) 80 (249 ) 121 (31 ) 90 (344 ) 84 (260 ) 6,222 (1,852 ) 4,370 Total other comprehensive income (loss) $ 21,197 $ (5,182 ) $ 16,015 $ (14,628 ) $ 4,021 $ (10,607 )	Accumulated Other Comprehensive Loss (“AOCL”): The components of AOCL are summarized as follows using applicable blended average federal and state tax rates for each period: December 31, 2018 December 31, 2017 (in thousands) Before Tax Tax Net of Tax Before Tax Tax Net of Tax Unrealized losses on available for sale securities $ (33,145 ) $ 8,104 $ (25,041 ) $ (13,414 ) $ 2,883 $ (10,531 ) Unrealized gains on interest rate swaps designated as cash flow hedges 9,103 (2,226 ) $ 6,877 5,602 (1,204 ) 4,398 Total AOCL $ (24,042 ) $ 5,878 $ (18,164 ) $ (7,812 ) $ 1,679 $ (6,133 ) The components of other comprehensive income (loss) for the three-year period ended December 31, 2018 is summarized as follows: December 31, 2018 (in thousands) Before Tax Tax Net of Tax Unrealized losses on available for sale securities: Change in fair value arising during the period $ (20,730 ) $ 5,465 $ (15,265 ) Reclassification adjustment for net losses included in net income 999 (244 ) 755 (19,731 ) 5,221 (14,510 ) Unrealized gains on interest rate swaps designated as cash flow hedges: Change in fair value arising during the period 3,744 (1,081 ) 2,663 Reclassification adjustment for net interest income included in net income (243 ) 59 (184 ) 3,501 (1,022 ) 2,479 Total other comprehensive loss $ (16,230 ) $ 4,199 $ (12,031 ) December 31, 2017 (in thousands) Before Tax Tax Net of Tax Unrealized gains on available for sale securities arising during the period $ 6,875 $ (3,298 ) $ 3,577 Reclassification adjustment for net losses on sale of securities included in net income 1,601 (768 ) 833 Unrealized gains on interest rate swaps designated as cash flow hedges 293 (141 ) 152 Total other comprehensive income $ 8,769 $ (4,207 ) $ 4,562 December 31, 2016 (in thousands) Before Tax Tax Net of Tax Unrealized losses on available for sale securities arising during the period $ (5,952 ) $ 2,113 $ (3,839 ) Reclassification adjustment for net gains on sale of securities included in net income (1,556 ) 552 (1,004 ) Unrealized gains on interest rate swaps designated as cash flow hedges 5,578 (1,980 ) 3,598 Total other comprehensive loss $ (1,930 ) $ 685 $ (1,245 )

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company was a wholly-owned subsidiary of MSF through August 10, 2018 when The Distributed Shares were distributed to MSF’s shareholders. MSF sold all of its voting Class A common stock in the IPO, and reduced its nonvoting Class B common stock to less than 5% of the Company’s total common stock on December 28, 2018. As a result, at year end 2018, MSF no longer controlled the Company or the Bank. Entities that are part of the MSF group outside the U.S. were related parties during most of 2018. Transactions with related parties are entered into pursuant to the Company’s policies and procedures, and Federal Reserve Regulation W, on substantially the same terms and conditions as transactions with unaffiliated third parties. In addition to loans to related parties and associated interest income, which are described below, included in the consolidated balance sheets and the consolidated statements of operations are amounts with related parties as follows: December 31, (in thousands) 2018 2017 Liabilities Demand deposits, noninterest bearing $ 9,447 $ 24,879 Demand deposits, interest bearing 3,721 21,071 Money market 308 449 Time deposits and accounts payable 1,350 7,636 Total due to related parties $ 14,826 $ 54,035 Years Ended December 31, (in thousands) 2018 2017 2016 Income Data processing and other services $ 2,168 $ 1,532 $ 2,328 Rental income from operating lease 248 1,971 1,976 Service charges 95 90 83 $ 2,511 $ 3,593 $ 4,387 Expenses Interest expense $ 126 $ 85 $ 73 Loss on sale of securities — — 796 Fees and other expenses 623 302 504 749 387 1,373 $ 1,762 $ 3,206 $ 3,014 Securities transactions On December 29, 2018, the Company repurchased Class B common stock from MSF. See Note 15 for more details. In 2016, the Company sold securities guaranteed by the government of Venezuela to a non-U.S. affiliate at their fair value of approximately $11.8 million and realized a loss on the sale of approximately $0.8 million . Such securities had been held by the Company as available for sale. Loan transactions The Company originates loans in the normal course of business to certain related parties. At December 31, 2018 and 2017, these loans amounted to $5.6 million and $4.8 million , respectively. These loans are generally made to persons who participate or have authority to participate (other than in the capacity of a director) in major policymaking functions of the Company or its affiliates, such as principal owners and management of the entity and their immediate families. Interest income on these loans was approximately $0.2 million in 2018 and 2017. In 2016, the Company purchased from the Bank a non-performing loan to a Canadian oil company’s Colombian operation at its fair value at the time of the transaction. Subsequently, the Company sold to a non-U.S. affiliate shares received in a restructuring of the same loan at their estimated fair value of approximately $4.9 million , which was included in other assets in the cash flow statement. The Company realized no gain or loss on sale of such shares. For the years ended December 31, 2018 and 2017, participations in corporate financial institution loans that were sold to non-U.S. affiliates amounted to approximately $10 million and $45 million , respectively. These participated loans were made to unaffiliated borrowers under terms consistent with the Company’s normal lending practices. The Company recorded no gain or loss on these loan participation transactions. There were no participations purchased from affiliates in 2018 and 2017. Services provided and received The Company has provided certain data processing and corporate services to non-U.S. affiliates under the terms of certain services agreements. Fee income for those services are included in data processing and other fees above. MSF has granted us a two-year license under our Amended and Restated Separation and Distribution Agreement dated as of June 12, 2018, commencing on August 18, 2018, to use the “Mercantil” name and marks in connection with our business. All such use must be in accordance with MSF’s current use policies. No fees are payable for the first year of the license. After the first year, the Company is obligated to pay a license fee monthly, at an annual rate equal to the lesser of $400,000 or the fair value of the license as determined by an independent appraisal consistent with Federal Reserve Regulation W. Payments under this license will cease when we terminate the use of the name and mark. We do not expect to pay any license fees to MSF. In 2018, the Company entered into a custody agreement and an information agent agreement with an MSF’s wholly owned Venezuela bank, and MSF, respectively. As a service to its smaller shareholders and to promote shareholder liquidity generally, the Company pays fees to be agreed on a per account fee for serving as custodian and transaction fees for assisting with changes in share ownership, including distribution of any payments from the Company in respect of Company shares that may be repurchased. The agreements provide for monthly fees payable by the Company and have an initial term of one year, subject to renewal for an additional year, and may be terminated earlier. Leasing subsidiary On February 15, 2018, the Company sold its membership interest in G200 Leasing, LLC (“G200 Leasing”) to a non-U.S. affiliate subsidiary of MSF. Prior to the sale, G200 Leasing distributed $19.8 million in cash to the Bank. All of the membership interests in G200 Leasing were sold for $8.5 million , which approximated the fair value of net assets sold. Net assets sold were mainly comprised of approximately $1 million cash held at the Bank and approximately $7.5 million corresponding to the net book value of an aircraft owned by G200 Leasing . The Company recorded no gain or loss on this sale. G200 Leasing had leased its aircraft to MSF. Under the terms of the lease agreement between G200 Leasing and MSF, MSF had sole use of the aircraft and provided for all of its scheduled maintenance, including maintaining sufficient qualified collateral in accordance with U.S. banking regulatory requirements. MSF had time deposits with the Company sufficient to meet those collateral requirements. Income from this lease agreement was included in rental income from the operating lease in the table above. Dividends paid On March 13, 2018, the Company paid a special, one-time, cash dividend of $40.0 million to MSF, or $0.94 per common share, in connection with the Spin-off.

Stockholders_ Equity

Stockholders’ Equity	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Stockholders’ Equity	Stockholders’ Equity a) Class A Common Stock Shares of the Company’s Class A common stock issued and outstanding as of March 31, 2019 and December 31, 2018 were 28,985,996 and 26,851,832 , respectively. IPO Over-allotment Option On January 23, 2019, the underwriters of the Company’s IPO partially exercised their over-allotment option by purchasing 229,019 shares of the Company’s Class A common stock at the public offering price of $13.00 per shares of Class A common stock. The net proceeds to the Company from this transaction were approximately $3.0 million . MSF agreed to pay all underwriting discounts, commissions and offering expenses with respect to the IPO, including the over-allotment option. Private Placements On February 1, 2019 and February 28, 2019, the Company issued and sold 153,846 and 1,750,000 shares of its Class A common stock, respectively, in private placements exempt from registration under Section 4(a)(2) of the Securities Act and Securities and SEC Rule 506 (the “Private Placements”). The net proceeds to the Company from the Private Placements totaled approximately $26.7 million . b) Class B Common Stock and Treasury Stock Shares of the Company’s Class B common stock issued as of March 31, 2019 and December 31, 2018 were 17,751,053 . As of March 31, 2019 and December 31, 2018, there were 14,218,596 shares and 16,330,917 shares of Class B common stock outstanding. As of March 31, 2019 and December 31, 2018, the Company had 3,532,457 shares and 1,420,136 shares of Class B common stock, respectively, held as treasury stock under the cost method. On March 7, 2019, the Company repurchased all of MSF’s 2,112,321 remaining shares of nonvoting Class B common stock at a weighted average price of $13.48 per share with proceeds from the IPO over-allotment exercise and the Private Placements, representing an aggregate purchase price of approximately $28.5 million . The aforementioned 2,112,321 shares of Class B common stock are held in treasury stock under the cost method. Following this repurchase, MSF no longer owns any shares of the Company’s Class A common stock or Class B common stock. Additionally, MSF no longer has any rights to register Company shares for resale. e) Dividends On March 13, 2018, the Company paid a special, one-time, cash dividend of $40.0 million to MSF, or $0.94 per common share.	Stockholders’ Equity (a) Amended and Restated Articles of Incorporation On February 6, 2018, the Company filed amended and restated articles of incorporation with the Secretary of State of Florida. Pursuant to the amended and restated articles, the total number of authorized Company shares of all classes is 550,000,000 , consisting of the following classes: Class Number of Par Value Common Stock: Class A 400,000,000 $ 0.10 Class B 100,000,000 0.10 500,000,000 Preferred Stock 50,000,000 0.10 550,000,000 Common Stock Holders of shares of Class A common stock and shares of Class B common stock have identical rights in all respects other than voting rights. Shares of Class B common stock are not convertible into shares of Class A common stock or vice versa. Holders of shares of Class A common stock are entitled to one vote per share on all matters. Holders of Class B common stock are entitled to one-tenth of a vote per share of Class B common stock, voting (i) together with the Class A common stock as a single voting group on proposals to appoint the Company’s independent auditors, if the Company seeks such a vote, (ii) as required by the Florida Business Corporation Act, and (iii) as a single voting group in other circumstances, including a reorganization event that adversely affects the rights of the Class B common stock. Preferred Stock The Board of Directors is authorized to provide for and designate, out of the authorized but unissued shares of Preferred Stock, one or more series of Preferred Stock and, with respect to each such series, to fix the number of shares, the price, dividend rates, rights, preferences, privileges and restrictions, including voting rights, of one or more series of preferred stock from time to time, without any vote or further action by the shareholders. There are currently no outstanding shares of preferred stock. Dividends Dividends shall be payable only when, as and if declared by the Board of Directors from lawful available funds, and may be paid in cash, property, or shares of any class or series or other securities or evidences of indebtedness of the Company or any other issuer, as may be determined by resolution or resolutions of the Board of Directors. Shares of Class B common stock are not entitled to receive dividends or distributions payable in shares of Class A common stock. b) Stock Splits On February 6, 2018, the Company exchanged 100% of the 298,570,328 shares of Class A common stock and 215,188,764 shares of Class B common stock outstanding, for 74,212,408 shares of Class A common stock and 53,253,157 shares of Class B common stock (the “Exchange”). This facilitated the distribution in the Spin-off of one share of Class A and Class B common stock for each outstanding share of MSF Class A and Class B common stock, respectively. On October 23, 2018, the Company completed a 1-for-3 reverse stock split of the Company’s issued and outstanding shares of its Class A and Class B common stock (the “Stock Split”). As a result of the Stock Split, every three shares of issued and outstanding Class A common stock were combined into one issued and outstanding share of Class A common stock, and every three shares of issued and outstanding Class B common stock were combined into one issued and outstanding share of Class B common stock, without any change in the par value per share. Fractional shares were issued and no cash was paid by the Company in respect of fractional shares or otherwise in the Stock Split. The Stock Split reduced the number of shares of Class A common stock issued and outstanding from 74,212,408 shares to 24,737,470 shares, and reduced the number of shares of Class B common stock issued and outstanding from 53,253,157 shares to 17,751,053 shares. As a result of the rebranding discussed in Note 1 to these consolidated financial statements, and in connection with the Stock Split, the Company's Class A and Class B common stock began trading on a Stock Split-adjusted basis on October 24, 2018 under the symbols “AMTB” (for the Class A shares) and “AMTBB” (for the Class B shares). The Company’s Class A and Class B shares had previously traded under the symbols “MBNA” and “MBNAA”, respectively. All references made to share or per share amounts in the consolidated financial statements for the periods presented and applicable disclosures have been retroactively adjusted to reflect the Exchange and Stock Split. In addition, as a result of the Exchange and Stock Split, the Company reclassified an amount equal to the reduction in the number of Company Shares at par value to additional paid-in capital on its consolidated financial statements for the periods presented. c) Class A Common Stock Shares of the Company’s Class A common stock issued and outstanding as of December 31, 2018 and 2017 were 26,851,832 and 24,737,470 , respectively. IPO On December 21, 2018, the Company closed the IPO of 6,300,000 shares of its Class A common stock at a public offering price of $13.00 per share. Of the 6,300,000 shares of Class A common stock sold in the offering, the Company sold 1,377,523 shares of Class A common stock and MSF sold all of its 4,922,477 shares of Class A common stock. In addition, the Company granted the underwriters a 30 -day option to purchase up to an additional 945,000 shares of Class A common stock at the public offering price, less the underwriting discount, to cover over-allotment. The net proceeds to the Company from the sale of its shares of Class A common stock in the IPO were approximately $17.9 million . The Company received no proceeds from the sale of its shares of Class A common stock in the IPO by MSF. On January 23, 2019, the Underwriters partially exercised their over-allotment option by purchasing 229,019 shares of the Company’s Class A common stock at the public offering price of $13.00 per shares of Class A common stock. The net proceeds to the Company from this transaction were approximately $3.0 million . MSF agreed to pay all underwriting discounts, commissions and offering expenses with respect to the IPO. Private Placements On February 1, 2019 and February 28, 2019, the Company issued and sold 153,846 and 1,750,000 shares of its Class A common stock, respectively, in private placements exempt from registration under Section 4(a)(2) of the Securities Act and Securities and SEC Rule 506 (the “Private Placements”). The net proceeds to the Company from the Private Placements totaled approximately $26.7 million . Stock Compensation Award On December 21, 2018, in connection with the closing of the Company’s IPO, the Company’s directors were granted restricted stock units, and various Company officers and employees were granted restricted Class A common stock awards, under the 2018 Equity Plan. Under this plan, the Company issued an aggregate of 736,839 shares of restricted stock during 2018. Refer to Note 11 to our consolidated financial statements for additional information about common stock transactions under the 2018 Equity Plan. d) Class B Common Stock and Treasury Stock Shares of the Company’s Class B common stock issued and outstanding as of December 31, 2018 and 2017 were 17,751,053 . On December 27, 2018, following the December 21, 2018 closing of the Company’s IPO, the Company and MSF entered into the Class B Purchase Agreement. Pursuant to the Class B Purchase Agreement, the Company agreed to purchase up to all 3,532,457 shares of its nonvoting Class B common stock from MSF using the net proceeds from the Company’s sale of its Class A common stock. On December 28, 2018, the Company completed the purchase of 1,420,136 shares of Class B common stock from MSF for $12.61 per shares of Class B common stock, representing an aggregate purchase price of approximately $17.9 million . The aforementioned 1,420,136 shares of Class B common stock are held in treasury stock under the cost method. On March 7, 2019, the Company repurchased all of MSF’s 2,112,321 remaining shares of nonvoting Class B common stock at a weighted average price of $13.48 per share with proceeds from the IPO over-allotment exercise and the Private Placements, representing an aggregate purchase price of approximately $28.5 million . The aforementioned 2,112,321 shares of Class B common stock are held in treasury stock under the cost method. e) Dividends On March 13, 2018, the Company paid a special, one-time, cash dividend of $40.0 million to MSF, or $0.94 per common share.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company and its subsidiaries are party to various legal actions arising in the ordinary course of business. In the opinion of management, the outcome of these proceedings will not have a significant effect on the Company’s consolidated financial position or results of operations. The Company occupies various premises under noncancelable lease agreements expiring through the year 2046. Actual rental expenses may include deferred rents that are recognized as rent expense on a straight line basis. Rent expense under these leases was approximately $1.6 million and $1.4 million for the three months ended March 31, 2019 and 2018 , respectively. Financial instruments whose contract amount represents off-balance sheet credit risk at March 31, 2019 are generally short-term and are as follows: (in thousands) Approximate Commitments to extend credit $ 884,142 Credit card facilities 196,901 Standby letters of credit 24,278 Commercial letters of credit 2,589 $ 1,107,910	Commitments and Contingencies The Company and its subsidiaries are party to various legal actions arising in the ordinary course of business. In the opinion of management, the outcome of these proceedings will not have a significant effect on the Company’s consolidated financial position or results of operations. The Company occupies various premises under noncancelable lease agreements expiring through the year 2046. Actual rental expenses may include deferred rents that are recognized as rent expense on a straight line basis. Rent expense under these leases was approximately $6 million for each of the years ended December 31, 2018, 2017 and 2016, respectively. Future minimum annual lease payments under such leases are as follows: Years Approximate (in thousands) 2019 $ 6,281 2020 6,223 2021 5,930 2022 5,386 2023 5,069 Thereafter 43,071 $ 71,960 The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit, credit card facilities and letters of credit. The Company’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for loan commitments and letters of credit is represented by the contractual amount of those instruments. The Company uses the same credit policies in making loan commitments and letters of credit as it does for on-balance sheet instruments. The Company controls the credit risk of loan commitments and letters of credit through credit approvals, customer limits, and monitoring procedures. Loan commitments are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Loan commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. The Company evaluates each customer’s credit-worthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Company upon extension of credit, is based on management’s credit evaluation. Collateral held varies but may include cash, accounts receivable, inventory, property and equipment, real estate in varying stages of development and occupancy, and income-producing commercial properties. Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support borrowing arrangements. They generally have one year terms and are renewable annually, if agreed. The credit risk involved in issuing standby letters of credit is generally the same as that involved in extending loan facilities to customers. The Company generally holds deposits, investments and real estate as collateral supporting those commitments. The extent of collateral held for those commitments at December 31, 2018 ranges from unsecured commitments to commitments fully collateralized by cash and securities. Commercial letters of credit are conditional commitments issued by the Company to guarantee payment by a customer to a third party, and are used primarily for importing or exporting goods and are terminated when proper payment is made by the customer. Credit card facilities represent the unused balance of the customers’ available credit card lines, and correspond to the maximum possible credit risk to the Company should customers draw upon their available credit card lines. We have not experienced and do not anticipate that all of our customers will access their entire available line at any given point in time. Financial instruments whose contract amount represents off-balance sheet credit risk at December 31, 2018 are generally short-term and are as follows: (in thousands) Approximate Commitments to extend credit $ 923,424 Credit card facilities 198,500 Standby letters of credit 19,562 Commercial letters of credit 7,670 $ 1,149,156

Fair Value Measurements

Fair Value Measurements	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Assets and liabilities measured at fair value on a recurring basis are summarized below: March 31, 2019 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 890,458 $ — $ 890,458 Corporate debt securities — 258,342 — 258,342 U.S. government agency debt securities — 215,336 — 215,336 Municipal bonds — 163,988 — 163,988 Mutual funds — 23,467 — 23,467 — 1,551,591 — 1,551,591 Bank owned life insurance — 207,546 — 207,546 Derivative instruments — 4,991 — 4,991 $ — $ 1,764,128 $ — $ 1,764,128 Liabilities Derivative instruments $ — $ 4,991 $ — $ 4,991 December 31, 2018 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 820,779 $ — $ 820,779 Corporate debt securities — 352,555 — 352,555 U.S. government agency debt securities — 216,985 — 216,985 Municipal bonds — 160,212 — 160,212 Mutual funds — 23,110 — 23,110 Commercial paper — 12,410 — 12,410 — 1,586,051 — 1,586,051 Bank owned life insurance — 206,141 — 206,141 Derivative instruments — 11,491 — 11,491 $ — $ 1,803,683 $ — $ 1,803,683 Liabilities Derivative instruments $ — $ 2,388 $ — $ 2,388 At the dates shown, there were no Level 3 assets or liabilities. Level 2 Valuation Techniques The valuation of securities and derivative instruments is performed through a monthly pricing process using data provided by generally recognized providers of independent data pricing services (the “Pricing Providers”). These Pricing Providers collect, use and incorporate descriptive market data from various sources, quotes and indicators from leading broker dealers to generate independent and objective valuations. The fair value of bank-owned life insurance policies is based on the cash surrender values of the policies as reported by the insurance companies. The valuation techniques and the inputs used in our consolidated financial statements to measure the fair value of our recurring Level 2 financial instruments consider, among other factors, the following: • Similar securities actively traded which are selected from recent market transactions; • Observable market data which includes spreads in relationship to LIBOR, swap curve, and prepayment speed rates, as applicable. • The captured spread and prepayment speed are used to obtain the fair value for each related security. On a quarterly basis, the Company evaluates the reasonableness of the monthly pricing process for the valuation of securities and derivative instruments. This evaluation includes challenging a random sample of the different types of securities in the investment portfolio as of the end of the quarter selected. This challenge consists of obtaining from the Pricing Providers a document explaining the methodology applied to obtain their fair value assessments for each type of investment included in the sample selection. The Company then analyzes in detail the various inputs used in the fair value calculation, both observable and unobservable (e.g., prepayment speeds, yield curve benchmarks, spreads, delinquency rates). Management considers that the consistent application of this methodology allows the Company to understand and evaluate the categorization of its investment portfolio. The methods described above may produce a fair value calculation that may differ from the net realizable value or may not be reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of its financial instruments could result in different estimates of fair value at the reporting date. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis The following table presents the major category of assets measured at fair value on a nonrecurring basis at March 31, 2019 : March 31, 2019 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Other Unobservable Inputs (Level 3) Total Impairments Description Loans held for sale $ 9,968 $ — $ — $ — There were no assets or liabilities measured at fair value on a nonrecurring basis at December 31, 2018 . Loans Held for Sale The Company measures the impairment of loans held for sale based on the amount by which the carrying values of those loans exceed their fair values. The Company primarily uses independent third party quotes to measure any subsequent decline in the value of loans held for sale. As a consequence, the fair value of these loans held for sale are considered a Level 1 valuation. Fair Value of Financial Instruments The fair value of a financial instrument represents the price that would be received from its sale in an orderly transaction between market participants at the measurement date. The best indication of the fair value of a financial instrument is determined based upon quoted market prices. However, in many cases, there are no quoted market prices for the Company’s various financial instruments. As a result, the Company derives the fair value of the financial instruments held at the reporting period-end, in part, using present value or other valuation techniques. Those techniques are significantly affected by management’s assumptions, the estimated amount and timing of future cash flows and estimated discount rates included in present value and other techniques. The use of different assumptions could significantly affect the estimated fair values of the Company’s financial instruments. Accordingly, the net realized values could be materially different from the estimates presented below. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: • Because of their nature and short-term maturities, the carrying values of the following financial instruments were used as a reasonable estimate of their fair value: cash and cash equivalents, interest earning deposits with banks, variable-rate loans with re-pricing terms shorter than twelve months, demand and savings deposits, short-term time deposits and other borrowings. • The fair value of loans held for sale, securities, bank owned life insurance and derivative instruments, are based on quoted market prices, when available. If quoted market prices are unavailable, fair value is estimated using the pricing process described in Note 17 to the Company’s audited consolidated financial statements on the Form 10-K. • The fair value of commitments and letters of credit is based on the assumption that the Company will be required to perform on all such instruments. The commitment amount approximates estimated fair value. • The fair value of fixed-rate loans, advances from the FHLB, and junior subordinated debentures are estimated using a present value technique by discounting the future expected contractual cash flows using the current rates at which similar instruments would be issued with comparable credit ratings and terms at the measurement date. • The fair value of long-term time deposits, including certificates of deposit, is determined using a present value technique by discounting the future expected contractual cash flows using current rates at which similar instruments would be issued at the measurement date. The estimated fair value of financial instruments where fair value differs from carrying value are as follows: March 31, 2019 December 31, 2018 (in thousands) Carrying Estimated Carrying Estimated Financial assets Loans $ 2,792,815 $ 2,670,693 $ 2,850,015 $ 2,739,721 Financial liabilities Time deposits 1,770,303 1,772,212 1,745,025 1,740,752 Advances from the FHLB 1,070,000 1,074,596 1,166,000 1,167,213 Junior subordinated debentures 118,110 114,620 118,110 99,450	Fair Value Measurements Assets and liabilities measured at fair value on a recurring basis are summarized below: December 31, 2018 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 820,779 $ — $ 820,779 Corporate debt securities — 352,555 — 352,555 U.S. government agency debt securities — 216,985 — 216,985 Municipal bonds — 160,212 — 160,212 Mutual funds — 23,110 — 23,110 Commercial paper — 12,410 — 12,410 — 1,586,051 — 1,586,051 Bank owned life insurance — 206,141 — 206,141 Derivative instruments — 11,491 — 11,491 $ — $ 1,803,683 $ — $ 1,803,683 Liabilities Derivative instruments $ — $ 2,388 $ — $ 2,388 December 31, 2017 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 875,666 $ — $ 875,666 Corporate debt securities — 313,392 — 313,392 U.S. government agency debt securities — 291,385 — 291,385 Municipal bonds — 180,396 — 180,396 Mutual funds — 23,617 — 23,617 U.S. treasury securities — 2,701 — 2,701 — 1,687,157 — 1,687,157 Bank owned life insurance — 200,318 — 200,318 Derivative instruments — 7,032 — 7,032 $ — $ 1,894,507 $ — $ 1,894,507 Liabilities Derivative instruments $ — $ 1,570 $ — $ 1,570 Level 2 Valuation Techniques The valuation of securities and derivative instruments is performed through a monthly pricing process using data provided by generally recognized providers of independent data pricing services (the “Pricing Providers”). These Pricing Providers collect, use and incorporate descriptive market data fro m various sources, quotes and indicators from leading broker dealers to generate independent and objective valuations. The fair value of bank-owned life insurance policies is based on the cash surrender values of the policies as reported by the insurance companies. The valuation techniques and the inputs used in our consolidated financial statements to measure the fair value of our recurring Level 2 financial instruments consider, among other factors, the following: • Similar securities actively traded which are selected from recent market transactions; • Observable market data which includes spreads in relationship to LIBOR, swap curve, and prepayment speed rates, as applicable. • The captured spread and prepayment speed is used to obtain the fair value for each related security. On a quarterly basis, the Company evaluates the reasonableness of the monthly pricing process for the valuation of securities and derivative instruments. This evaluation includes challenging a random sample of the different types of securities in the investment portfolio as of the end of the quarter selected. This challenge consists of obtaining from the Pricing Providers a document explaining the methodology applied to obtain their fair value assessments for each type of investment included in the sample selection. The Company then analyzes in detail the various inputs used in the fair value calculation, both observable and unobservable (e.g., prepayment speeds, yield curve benchmarks, spreads, delinquency rates). Management considers that the consistent application of this methodology allows the Company to understand and evaluate the categorization of its investment portfolio. The methods described above may produce a fair value calculation that may differ from the net realizable value or may not be reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of its financial instruments could result in different estimates of fair value at the reporting date. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis There were no significant assets or liabilities measured at fair value on a nonrecurring basis at December 31, 2018 . The following table presents the major category of assets measured at fair value on a nonrecurring basis at December 31, 2017 : December 31, 2017 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Other Unobservable Inputs (Level 3) Total Impairments Description Loans held for sale $ 5,611 $ — $ — $ — Loans Held for Sale The Company measures the impairment of loans held for sale based on the amount by which the carrying values of those loans exceed their fair values. The Company primarily uses independent third party quotes to measure any subsequent decline in the value of loans held for sale. As a consequence, the fair value of these loans held for sale are considered a Level 1 valuation. Fair Value of Financial Instruments The fair value of a financial instrument represents the price that would be received from its sale in an orderly transaction between market participants at the measurement date. The best indication of the fair value of a financial instrument is determined based upon quoted market prices. However, in many cases, there are no quoted market prices for the Company’s various financial instruments. As a result, the Company derives the fair value of the financial instruments held at the reporting period-end, in part, using present value or other valuation techniques. Those techniques are significantly affected by management’s assumptions, the estimated amount and timing of future cash flows and estimated discount rates included in present value and other techniques. The use of different assumptions could significantly affect the estimated fair values of the Company’s financial instruments. Accordingly, the net realized values could be materially different from the estimates presented below. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: • Because of their nature and short-term maturities, the carrying values of the following financial instruments were used as a reasonable estimate of their fair value: cash and cash equivalents, interest earning deposits with banks, variable-rate loans with re-pricing terms shorter than twelve months, demand and savings deposits, short-term time deposits and other borrowings. • The fair value of loans held for sale, securities, bank owned life insurance and derivative instruments, are based on quoted market prices, when available. If quoted market prices are unavailable, fair value is estimated using the pricing process described in Note 17. • The fair value of commitments and letters of credit is based on the assumption that the Company will be required to perform on all such instruments. The commitment amount approximates estimated fair value. • The fair value of fixed-rate loans, advances from the FHLB, and junior subordinated debentures are estimated using a present value technique by discounting the future expected contractual cash flows using the current rates at which similar instruments would be issued with comparable credit ratings and terms at the measurement date. • The fair value of long-term time deposits, including certificates of deposit, is determined using a present value technique by discounting the future expected contractual cash flows using current rates at which similar instruments would be issued at the measurement date. The estimated fair value of financial instruments where fair value differs from carrying value are as follows: December 31, 2018 December 31, 2017 (in thousands) Carrying Estimated Carrying Estimated Financial assets Loans $ 2,850,015 $ 2,739,721 $ 2,682,790 $ 2,566,197 Financial liabilities Time deposits 1,745,025 1,740,752 1,466,464 1,461,908 Advances from the Federal Home Loan Bank 1,166,000 1,167,213 1,161,000 1,164,686 Junior subordinated debentures 118,110 99,450 118,110 95,979

Fair Value of Financial Instrum

Fair Value of Financial Instruments	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value Measurements Assets and liabilities measured at fair value on a recurring basis are summarized below: March 31, 2019 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 890,458 $ — $ 890,458 Corporate debt securities — 258,342 — 258,342 U.S. government agency debt securities — 215,336 — 215,336 Municipal bonds — 163,988 — 163,988 Mutual funds — 23,467 — 23,467 — 1,551,591 — 1,551,591 Bank owned life insurance — 207,546 — 207,546 Derivative instruments — 4,991 — 4,991 $ — $ 1,764,128 $ — $ 1,764,128 Liabilities Derivative instruments $ — $ 4,991 $ — $ 4,991 December 31, 2018 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 820,779 $ — $ 820,779 Corporate debt securities — 352,555 — 352,555 U.S. government agency debt securities — 216,985 — 216,985 Municipal bonds — 160,212 — 160,212 Mutual funds — 23,110 — 23,110 Commercial paper — 12,410 — 12,410 — 1,586,051 — 1,586,051 Bank owned life insurance — 206,141 — 206,141 Derivative instruments — 11,491 — 11,491 $ — $ 1,803,683 $ — $ 1,803,683 Liabilities Derivative instruments $ — $ 2,388 $ — $ 2,388 At the dates shown, there were no Level 3 assets or liabilities. Level 2 Valuation Techniques The valuation of securities and derivative instruments is performed through a monthly pricing process using data provided by generally recognized providers of independent data pricing services (the “Pricing Providers”). These Pricing Providers collect, use and incorporate descriptive market data from various sources, quotes and indicators from leading broker dealers to generate independent and objective valuations. The fair value of bank-owned life insurance policies is based on the cash surrender values of the policies as reported by the insurance companies. The valuation techniques and the inputs used in our consolidated financial statements to measure the fair value of our recurring Level 2 financial instruments consider, among other factors, the following: • Similar securities actively traded which are selected from recent market transactions; • Observable market data which includes spreads in relationship to LIBOR, swap curve, and prepayment speed rates, as applicable. • The captured spread and prepayment speed are used to obtain the fair value for each related security. On a quarterly basis, the Company evaluates the reasonableness of the monthly pricing process for the valuation of securities and derivative instruments. This evaluation includes challenging a random sample of the different types of securities in the investment portfolio as of the end of the quarter selected. This challenge consists of obtaining from the Pricing Providers a document explaining the methodology applied to obtain their fair value assessments for each type of investment included in the sample selection. The Company then analyzes in detail the various inputs used in the fair value calculation, both observable and unobservable (e.g., prepayment speeds, yield curve benchmarks, spreads, delinquency rates). Management considers that the consistent application of this methodology allows the Company to understand and evaluate the categorization of its investment portfolio. The methods described above may produce a fair value calculation that may differ from the net realizable value or may not be reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of its financial instruments could result in different estimates of fair value at the reporting date. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis The following table presents the major category of assets measured at fair value on a nonrecurring basis at March 31, 2019 : March 31, 2019 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Other Unobservable Inputs (Level 3) Total Impairments Description Loans held for sale $ 9,968 $ — $ — $ — There were no assets or liabilities measured at fair value on a nonrecurring basis at December 31, 2018 . Loans Held for Sale The Company measures the impairment of loans held for sale based on the amount by which the carrying values of those loans exceed their fair values. The Company primarily uses independent third party quotes to measure any subsequent decline in the value of loans held for sale. As a consequence, the fair value of these loans held for sale are considered a Level 1 valuation. Fair Value of Financial Instruments The fair value of a financial instrument represents the price that would be received from its sale in an orderly transaction between market participants at the measurement date. The best indication of the fair value of a financial instrument is determined based upon quoted market prices. However, in many cases, there are no quoted market prices for the Company’s various financial instruments. As a result, the Company derives the fair value of the financial instruments held at the reporting period-end, in part, using present value or other valuation techniques. Those techniques are significantly affected by management’s assumptions, the estimated amount and timing of future cash flows and estimated discount rates included in present value and other techniques. The use of different assumptions could significantly affect the estimated fair values of the Company’s financial instruments. Accordingly, the net realized values could be materially different from the estimates presented below. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: • Because of their nature and short-term maturities, the carrying values of the following financial instruments were used as a reasonable estimate of their fair value: cash and cash equivalents, interest earning deposits with banks, variable-rate loans with re-pricing terms shorter than twelve months, demand and savings deposits, short-term time deposits and other borrowings. • The fair value of loans held for sale, securities, bank owned life insurance and derivative instruments, are based on quoted market prices, when available. If quoted market prices are unavailable, fair value is estimated using the pricing process described in Note 17 to the Company’s audited consolidated financial statements on the Form 10-K. • The fair value of commitments and letters of credit is based on the assumption that the Company will be required to perform on all such instruments. The commitment amount approximates estimated fair value. • The fair value of fixed-rate loans, advances from the FHLB, and junior subordinated debentures are estimated using a present value technique by discounting the future expected contractual cash flows using the current rates at which similar instruments would be issued with comparable credit ratings and terms at the measurement date. • The fair value of long-term time deposits, including certificates of deposit, is determined using a present value technique by discounting the future expected contractual cash flows using current rates at which similar instruments would be issued at the measurement date. The estimated fair value of financial instruments where fair value differs from carrying value are as follows: March 31, 2019 December 31, 2018 (in thousands) Carrying Estimated Carrying Estimated Financial assets Loans $ 2,792,815 $ 2,670,693 $ 2,850,015 $ 2,739,721 Financial liabilities Time deposits 1,770,303 1,772,212 1,745,025 1,740,752 Advances from the FHLB 1,070,000 1,074,596 1,166,000 1,167,213 Junior subordinated debentures 118,110 114,620 118,110 99,450	Fair Value Measurements Assets and liabilities measured at fair value on a recurring basis are summarized below: December 31, 2018 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 820,779 $ — $ 820,779 Corporate debt securities — 352,555 — 352,555 U.S. government agency debt securities — 216,985 — 216,985 Municipal bonds — 160,212 — 160,212 Mutual funds — 23,110 — 23,110 Commercial paper — 12,410 — 12,410 — 1,586,051 — 1,586,051 Bank owned life insurance — 206,141 — 206,141 Derivative instruments — 11,491 — 11,491 $ — $ 1,803,683 $ — $ 1,803,683 Liabilities Derivative instruments $ — $ 2,388 $ — $ 2,388 December 31, 2017 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 875,666 $ — $ 875,666 Corporate debt securities — 313,392 — 313,392 U.S. government agency debt securities — 291,385 — 291,385 Municipal bonds — 180,396 — 180,396 Mutual funds — 23,617 — 23,617 U.S. treasury securities — 2,701 — 2,701 — 1,687,157 — 1,687,157 Bank owned life insurance — 200,318 — 200,318 Derivative instruments — 7,032 — 7,032 $ — $ 1,894,507 $ — $ 1,894,507 Liabilities Derivative instruments $ — $ 1,570 $ — $ 1,570 Level 2 Valuation Techniques The valuation of securities and derivative instruments is performed through a monthly pricing process using data provided by generally recognized providers of independent data pricing services (the “Pricing Providers”). These Pricing Providers collect, use and incorporate descriptive market data fro m various sources, quotes and indicators from leading broker dealers to generate independent and objective valuations. The fair value of bank-owned life insurance policies is based on the cash surrender values of the policies as reported by the insurance companies. The valuation techniques and the inputs used in our consolidated financial statements to measure the fair value of our recurring Level 2 financial instruments consider, among other factors, the following: • Similar securities actively traded which are selected from recent market transactions; • Observable market data which includes spreads in relationship to LIBOR, swap curve, and prepayment speed rates, as applicable. • The captured spread and prepayment speed is used to obtain the fair value for each related security. On a quarterly basis, the Company evaluates the reasonableness of the monthly pricing process for the valuation of securities and derivative instruments. This evaluation includes challenging a random sample of the different types of securities in the investment portfolio as of the end of the quarter selected. This challenge consists of obtaining from the Pricing Providers a document explaining the methodology applied to obtain their fair value assessments for each type of investment included in the sample selection. The Company then analyzes in detail the various inputs used in the fair value calculation, both observable and unobservable (e.g., prepayment speeds, yield curve benchmarks, spreads, delinquency rates). Management considers that the consistent application of this methodology allows the Company to understand and evaluate the categorization of its investment portfolio. The methods described above may produce a fair value calculation that may differ from the net realizable value or may not be reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of its financial instruments could result in different estimates of fair value at the reporting date. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis There were no significant assets or liabilities measured at fair value on a nonrecurring basis at December 31, 2018 . The following table presents the major category of assets measured at fair value on a nonrecurring basis at December 31, 2017 : December 31, 2017 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Other Unobservable Inputs (Level 3) Total Impairments Description Loans held for sale $ 5,611 $ — $ — $ — Loans Held for Sale The Company measures the impairment of loans held for sale based on the amount by which the carrying values of those loans exceed their fair values. The Company primarily uses independent third party quotes to measure any subsequent decline in the value of loans held for sale. As a consequence, the fair value of these loans held for sale are considered a Level 1 valuation. Fair Value of Financial Instruments The fair value of a financial instrument represents the price that would be received from its sale in an orderly transaction between market participants at the measurement date. The best indication of the fair value of a financial instrument is determined based upon quoted market prices. However, in many cases, there are no quoted market prices for the Company’s various financial instruments. As a result, the Company derives the fair value of the financial instruments held at the reporting period-end, in part, using present value or other valuation techniques. Those techniques are significantly affected by management’s assumptions, the estimated amount and timing of future cash flows and estimated discount rates included in present value and other techniques. The use of different assumptions could significantly affect the estimated fair values of the Company’s financial instruments. Accordingly, the net realized values could be materially different from the estimates presented below. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: • Because of their nature and short-term maturities, the carrying values of the following financial instruments were used as a reasonable estimate of their fair value: cash and cash equivalents, interest earning deposits with banks, variable-rate loans with re-pricing terms shorter than twelve months, demand and savings deposits, short-term time deposits and other borrowings. • The fair value of loans held for sale, securities, bank owned life insurance and derivative instruments, are based on quoted market prices, when available. If quoted market prices are unavailable, fair value is estimated using the pricing process described in Note 17. • The fair value of commitments and letters of credit is based on the assumption that the Company will be required to perform on all such instruments. The commitment amount approximates estimated fair value. • The fair value of fixed-rate loans, advances from the FHLB, and junior subordinated debentures are estimated using a present value technique by discounting the future expected contractual cash flows using the current rates at which similar instruments would be issued with comparable credit ratings and terms at the measurement date. • The fair value of long-term time deposits, including certificates of deposit, is determined using a present value technique by discounting the future expected contractual cash flows using current rates at which similar instruments would be issued at the measurement date. The estimated fair value of financial instruments where fair value differs from carrying value are as follows: December 31, 2018 December 31, 2017 (in thousands) Carrying Estimated Carrying Estimated Financial assets Loans $ 2,850,015 $ 2,739,721 $ 2,682,790 $ 2,566,197 Financial liabilities Time deposits 1,745,025 1,740,752 1,466,464 1,461,908 Advances from the Federal Home Loan Bank 1,166,000 1,167,213 1,161,000 1,164,686 Junior subordinated debentures 118,110 99,450 118,110 95,979

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2018
Banking and Thrift [Abstract]
Regulatory Matters	Regulatory Matters The Company and the Bank are subject to various regulatory requirements administered by federal banking agencies. The following is a summary of restrictions related to dividend payments and capital adequacy. Dividend Restrictions Dividends payable by the Bank as a national bank subsidiary of the Company, are limited by law and Office of the Comptroller of the Currency (“OCC”) regulations. A dividend may not be paid if the total of all dividends declared by a bank in any calendar year is in excess of the current year’s net income combined with the retained net income of the two preceding years, unless the national bank obtains the approval of the OCC. At December 31, 2018 and 2017, the Bank could pay dividends of $82.6 million and $84.4 million , respectively, without prior OCC approval. In addition, the Company and the Bank are subject to various general regulatory policies and requirements relating to the payment of dividends, including requirements to maintain capital above regulatory minimums and the maintenance of capital in excess of capital conservation buffers required by the Federal Reserve and OCC capital regulations. Capital Adequacy Under the Basel III capital and prompt corrective action rules, the Company and the Bank must meet specific capital guidelines that involve quantitative measures and qualitative judgments about capital components, risk weightings, and other factors. The Basel III rules became effective for the Company and the Bank on January 1, 2015 with full compliance with all of the requirements being phased in over a multi-year schedule and were fully phased in by January 1, 2019. The Company and the Bank opted to not include the AOCI or AOCL in computing regulatory capital. As of December 31, 2018, management believes that the Company and the Bank meet all capital adequacy requirements to which they are subject, and are well capitalized. In addition, the Company and the Bank must each hold a capital conservation buffer of 2.50% by 2019. The Company’s capital conservation buffer at year end 2018 and 2017 was 5.5% and 5.3% , respectively, and therefore no regulatory restrictions exist under the applicable capital rules on dividends or discretionary bonuses or other payments. The Bank’s actual capital amounts and ratios are presented in the following table: Actual Minimums Required for Capital Adequacy Purposes Regulatory Minimums to be Well Capitalized (in thousands, except percentages) Amount Ratio Amount Ratio Amount Ratio December 31, 2018 Total capital ratio $ 883,746 13.05 % $ 541,564 8.00 % $ 676,955 10.00 % Tier 1 capital ratio 826,114 12.20 % 406,173 6.00 % 541,564 8.00 % Tier 1 leverage ratio 826,114 9.96 % 331,829 4.00 % 414,786 5.00 % Common equity tier 1 (CET1) 826,114 12.20 % 304,630 4.50 % 440,021 6.50 % December 31, 2017 Total capital ratio $ 885,855 12.69 % $ 556,446 8.00 % $ 695,557 10.00 % Tier 1 capital ratio 812,631 11.68 % 417,334 6.00 % 556,446 8.00 % Tier 1 leverage ratio 812,631 9.69 % 335,600 4.00 % 419,500 5.00 % Common equity tier 1 (CET1) 812,631 11.68 % 313,001 4.50 % 452,112 6.50 % The Company’s actual capital amounts and ratios are presented in the following table: Actual Minimums Required for Capital Adequacy Purposes Regulatory Minimums To be Well Capitalized (in thousands, except percentages) Amount Ratio Amount Ratio Amount Ratio December 31, 2018 Total capital ratio $ 916,663 13.54 % $ 541,638 8.00 % $ 677,047 10.00 % Tier 1 capital ratio 859,031 12.69 % 406,228 6.00 % 541,638 8.00 % Tier 1 leverage ratio 859,031 10.34 % 332,190 4.00 % 415,238 5.00 % Common equity tier 1 (CET1) 749,465 11.07 % 304,671 4.50 % 440,080 6.50 % December 31, 2017 Total capital ratio $ 926,049 13.31 % $ 556,578 8.00 % $ 695,722 10.00 % Tier 1 capital ratio 852,825 12.21 % 417,433 6.00 % 556,578 8.00 % Tier 1 leverage ratio 852,825 10.15 % 335,647 4.00 % 419,559 5.00 % Common equity tier 1 (CET1) 753,545 10.68 % 313,075 4.50 % 452,220 6.50 %

Earnings Per Share

Earnings Per Share	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table shows the calculation of basic and diluted earnings per share: Three months ended March 31, (in thousands, except per share data) 2019 2018 Numerator: Net income available to common stockholders $ 13,071 $ 9,429 Denominator: Basic weighted average shares outstanding 42,755 42,489 Dilutive effect of share-based compensation awards 159 — Diluted weighted average shares outstanding 42,914 42,489 Basic earnings per common share $ 0.31 $ 0.22 Diluted earnings per common share $ 0.30 $ 0.22 As of March 31, 2019, potential dilutive instruments consist of 738,138 unvested shares of restricted stock, including 736,839 shares of restricted stock issued in December 2018 in connection with the Company’s IPO and 1,299 additional shares of restricted stock issued in January 2019. As of March 31, 2019, these 738,138 unvested shares of restricted stock were included in the diluted earnings per share computation because, when the unamortized deferred compensation cost related to these shares was divided by the average market price per share at that date, fewer shares would have been purchased than restricted shares assumed issued. Therefore, at that date, such awards had a dilutive effect. As of March 31, 2018, the Company had no potentially dilutive instruments.	Earnings Per Share The following table shows the calculation of basic and diluted earnings per share: (in thousands, except per share data) 2018 2017 2016 Numerator: Net income available to common stockholders $ 45,833 $ 43,057 $ 23,579 Denominator: Basic weighted averages shares outstanding 42,487 42,489 42,489 Dilutive effect of shared-based compensation awards — — — Diluted weighted average shares outstanding 42,487 42,489 42,489 Basic earnings per common share $ 1.08 $ 1.01 $ 0.55 Diluted earnings per common share $ 1.08 $ 1.01 $ 0.55 As of December 31, 2018, 736,839 unvested shares of restricted stock were excluded from the diluted earnings per share computation because they would have an anti-dilutive effect. As of December 31, 2017 and 2016, the Company had no other outstanding or potentially dilutive instruments.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment Information	Segment Information Prior to the second quarter of 2019, the Company had four reportable segments: Personal and Commercial Banking (“PAC”), Corporate LATAM, Treasury and Institutional. Results of these segments were presented on a managed basis. This structure was driven, among other things, by how the Company previously managed the business, how internal reporting was prepared and analyzed, and how management made decisions. In August 2019, the Company announced that due to changes in the structure of its internal organization that it would report its financial performance as a single operating segment beginning with the quarter ended June 30, 2019. As a result of these changes, all decisions, including those relating to loan growth and concentrations, deposit and other funding, market risk, credit risk, operational risk and pricing are now made after assessing their effects on the Company as a whole, using a single segment concept.

Condensed Unconsolidated Holdin

Condensed Unconsolidated Holding Companies’ Financial Statements	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Condensed Unconsolidated Financial Statements	Condensed Unconsolidated Holding Companies’ Financial Statements The separate condensed unconsolidated financial statements of each of the Company and its wholly-owned subsidiary Mercantil Florida Bancorp, Inc. have been prepared using the same basis of accounting that the Company used to prepare its consolidated financial statements described in Note 1, except for its investment in subsidiaries which is accounted for using the equity method. Under the equity method, investments in subsidiaries are initially recorded at cost, and they are periodically adjusted due to changes in the interest of the parent company over the net assets of the subsidiaries. The Company records in the results for the period, its participation in the profit or loss of the subsidiaries, and in AOCL its participation in the “Other comprehensive income account” of the subsidiary. In applying the equity method the Company uses the subsidiaries consolidated financial statements at the end of the period prepared under U.S. GAAP. Condensed financial statements of Mercantil Bank Holding Corporation are presented below: Condensed Balance Sheets: December 31, (in thousands) 2018 2017 Assets Cash and due from banks $ 1,891 $ 1,420 Investments in subsidiaries 746,344 752,409 Other assets 1,720 1,798 $ 749,955 $ 755,627 Liabilities and Stockholders' Equity Other liabilities $ 2,537 $ 2,177 Stockholders' equity 747,418 753,450 $ 749,955 $ 755,627 Condensed Statements of Income: Years ended December 31 (in thousands) 2018 2017 2016 Income: Interest $ 9 $ 3 $ 2 Equity in earnings of subsidiary 53,939 45,008 23,996 Total income 53,948 45,011 23,998 Expenses: Employee compensation and benefit — 350 350 Other expenses 8,018 2,539 250 Total expense 8,018 2,889 600 Net income before income tax benefit 45,930 42,122 23,398 Income tax (expense) benefit (97 ) 935 181 Net income $ 45,833 $ 43,057 $ 23,579 Condensed Statements of Cash Flows: Years ended December 31, (in thousands) 2018 2017 2016 Cash flows from operating activities Net income $ 45,833 $ 43,057 $ 23,579 Adjustments to reconcile net income to net cash used in operating activities - Equity in earnings of subsidiaries (53,939 ) (45,008 ) (23,996 ) Net change in other assets and liabilities 438 1,337 (2 ) Net cash used in operating activities (7,668 ) (614 ) (419 ) Cash flows from investing activities Cash received upon Voting Trust termination 639 — — Dividends from subsidiary 47,500 700 400 Net cash provided by investment activities 48,139 700 400 Cash flows from financing activities Dividends paid (40,000 ) — — Common stock issued - Class A 17,908 — — Repurchase of common stock - Class B (17,908 ) — — Net cash used in financing activities (40,000 ) — — Net increase (decrease) in cash and cash equivalents 471 86 (19 ) Cash and cash equivalents Beginning of year 1,420 1,334 1,353 End of year $ 1,891 $ 1,420 $ 1,334 Investment in subsidiaries corresponds to the Company’s direct investment in Florida Bancorp in 2018 and the Company’s beneficial ownership of the Voting Trust in 2017. The Company had determined that it was the sole beneficial owner of the Voting Trust and consolidated the financial statements of the Voting Trust with its own financial statements for regulatory reporting purposes. In 2017, the Voting Trust wholly-owned Mercantil Florida Bancorp, Inc., which in turn wholly-owned the Bank and its subsidiaries. In 2018, the Voting Trust was terminated and ownership of Florida Bancorp, Inc. was assumed by the Company. Condensed financial statements of Mercantil Florida Bancorp, Inc are presented below: Condensed Balance Sheets: December 31, (in thousands) 2018 2017 Assets Cash and due from banks $ 32,922 $ 39,089 Investments in subsidiaries 822,940 821,982 Other assets 9,640 9,775 $ 865,502 $ 870,846 Liabilities and Stockholder’s Equity Junior subordinated debentures held by trust subsidiaries $ 118,110 $ 118,110 Other liabilities 1,048 979 Stockholder’s equity 746,344 751,757 $ 865,502 $ 870,846 Condensed Statements of Income: Years ended December 31 (in thousands) 2018 2017 2016 Income: Interest $ 182 $ 85 $ 33 Equity in earnings of subsidiary 60,609 50,982 31,282 Total income 60,791 51,067 31,315 Expenses: Interest Expense 8,086 7,456 7,129 Provision for loan losses — — 1,838 Other expenses 414 1,310 1,361 Total expense 8,500 8,766 10,328 Net income before income tax benefit 52,291 42,301 20,987 Income tax benefit 1,661 2,726 3,031 Net income $ 53,952 $ 45,027 $ 24,018 Condensed Statements of Cash Flows: Years ended December 31, (in thousands) 2018 2017 2016 Cash flows from operating activities Net income $ 53,952 $ 45,027 $ 24,018 Adjustments to reconcile net income to net cash used in operating activities - Equity in earnings of subsidiaries (60,609 ) (50,982 ) (31,282 ) Net change in other assets and liabilities 490 (4 ) (35 ) Net cash used in operating activities (6,167 ) (5,959 ) (7,299 ) Cash flows from investing activities Dividends received from subsidiary 47,500 6,000 6,000 Dividends paid (47,500 ) (700 ) (400 ) Net cash provided by investing activities — 5,300 5,600 Net decrease in cash and cash equivalents (6,167 ) (659 ) (1,699 ) Cash and cash equivalents Beginning of year 39,089 39,748 41,447 End of year $ 32,922 $ 39,089 $ 39,748

Business, Basis of Presentati_2

Business, Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Subsequent Events	Subsequent Events The effects of significant subsequent events, if any, have been recognized or disclosed in these unaudited interim consolidated financial statements.	Subsequent Events The effects of significant subsequent events, if any, have been recognized or disclosed in these consolidated financial statements.
Principles of Consolidation		Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
Estimates	Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates made by management include: (i) the determination of the allowance for loan losses; (ii) the fair values of securities and the reporting unit to which goodwill has been assigned during the annual goodwill impairment test; (iii) the cash surrender value of bank owned life insurance; and (iv) the determination of whether the amount of deferred tax assets will more likely than not be realized. Management believes that these estimates are appropriate. Actual results could differ from these estimates.	Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates made by management include: i) the determination of the allowance for loan losses; (ii) the fair values of securities and the reporting unit to which goodwill has been assigned during the annual goodwill impairment test; (iii) the cash surrender value of bank owned life insurance; and (iv) the determination of whether the amount of deferred tax assets will more likely than not be realized. Management believes that these estimates are appropriate. Actual results could differ from these estimates.
Income Recognition, Interest		Interest income is generally recognized on the accrual basis using the interest method. Non-refundable loan origination fees, net of direct costs of originating or acquiring loans, as well as loan purchase premiums and discounts, are deferred and amortized over the term of the related loans as adjustments to interest income using the level yield method. Purchase premiums and discounts on debt securities are amortized as adjustments to interest income over the estimated lives of the securities using the level yield method.
Income Recognition, Fees		Brokerage and advisory activities include brokerage commissions and advisory fees. Brokerage commissions earned are related to the dollar amount of trading volume of customers’ transactions. Commissions and related clearing expenses are recorded on a trade-date basis as securities transactions occur. Advisory fees are derived from investment advisory fees and account administrative services. Investment advisory fees are recorded as earned on a pro rata basis over the term of the contracts, based on a percentage of the average value of assets managed during the period. These fees are assessed and collected at least quarterly. Account administrative fees are charged to customers for the maintenance of their accounts and are earned and collected on a quarterly basis. Fiduciary activities fee income is recognized as earned on a pro rata basis over the term of contracts. Card servicing fees include credit card issuance and credit and debit card interchange fees. Credit card issuance fees are generally recognized over the period in which the cardholders are entitled to use the cards. Interchange fees are recognized when earned. Trade finance servicing fees, which primarily include commissions on letters of credit, are generally recognized over the service period on a straight line basis. Deposits and services fees include service charges on deposit accounts, fees for banking services provided to customers including wire transfers, overdrafts and non-sufficient funds. Revenue is generally recognized in accordance with published deposit account agreements for customer accounts or when fixed and determinable per contractual agreements. Data processing, rental income and fees for other services to related parties are recognized as the services are provided in accordance with the terms of the service agreements.
Earnings Per Share		Earnings per Share Basic earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of common shares outstanding during each period. Unvested shares of restricted stock are excluded from the basic earnings per share computation. Diluted net income per common share reflects the number of additional common stock that would have been outstanding if the dilutive potential common stock had been issued. Dilutive potential common stock consist of unvested shares of restricted stock outstanding during the period. The dilutive effect of potential common stock is calculated by applying the treasury stock method. The latter assumes dilutive potential common stock are issued and outstanding and the proceeds from the exercise, are used to purchase common stock at the average market price during the period. The difference between the numbers of dilutive potential common stock issued and the number of shares purchased is included as incremental shares in the denominator to compute diluted net income per common stock. Dilutive potential common stock are excluded from the diluted earnings per share computation in the period in which the effect is anti-dilutive. Changes in the number of shares outstanding as a result of stock dividends, stock splits, stock exchanges or reverse stock splits are given effect retroactively for all periods presented to reflect those changes in capital structure.
Stock-based Compensation		Stock-based Compensation The Company may grant share-based compensation and other related awards to its non-employee directors, officers, employees and certain consultants. Compensation cost is measured based on the estimated fair value of the award at the grant date and recognized in earnings on a straight -line basis over the requisite service period or vesting period. The fair value of the unvested shares of restricted stock is based on the market price of the Company’s Class A common stock at the date of the grant.
Advertising Expenses		Advertising Expenses Advertising expenses are expensed as incurred and are included in other noninterest expenses.
Offering Expenses		Offering Expenses Specific, non-reimbursable, incremental costs directly attributable to a proposed or actual securities offerings are deferred and charged against the gross proceeds of the offering.
Cash and Cash Equivalents		Cash and Cash Equivalents The Company has defined as cash equivalents those highly liquid instruments purchased with an original maturity of three months or less and include cash and cash due from banks, federal funds sold and deposits with banks. The Company must comply with federal regulations requiring the maintenance of minimum reserve balances against its deposits. At December 31, 2018 and 2017, these reserve balances amounted to approximately $0.2 million and $1.2 million , respectively.
Securities		Securities The Company classifies its investments in securities as available for sale and held to maturity. Securities classified as available for sale are carried at fair value with unrealized gains and losses included in accumulated other comprehensive income (“AOCI”) in stockholders’ equity on an after-tax basis. Securities classified as held to maturity are securities the Company has both the ability and intent to hold until maturity and are carried at amortized cost. Investments in stock issued by the Federal Reserve and Federal Home Loan Bank of Atlanta (“FHLB”) are stated at their original cost, which approximates their realizable value. Realized gains and losses from sales of securities are recorded on the trade date and are determined using the specific identification method. Securities purchased are recorded on the consolidated balance sheets as of the trade date. Receivables and payables to and from clearing organizations relating to outstanding transactions are included in other assets or other liabilities. At December 31, 2018 and 2017 securities receivables amounted to $3.5 million and $6.5 million , respectively. The Company considers an investment security to be impaired when a decline in fair value below the amortized cost basis is other-than-temporary. When an investment security is considered to be other-than-temporarily impaired, the cost basis of the individual investment security is written down through earnings by an amount that corresponds to the credit component of the other-than-temporary impairment. The amount of the other-than-temporary impairment that corresponds to the noncredit component of the other-than-temporary impairment is recorded in AOCI and is associated with securities which the Company does not intend to sell and it is more likely than not that the Company will not be required to sell the securities prior to the recovery of its fair value. The Company estimates the credit component of other-than-temporary impairment using a discounted cash flow model. The Company estimates the expected cash flows of the underlying collateral using third party vendor models that incorporate management’s best estimate of current key assumptions, such as default rates, loss severity and prepayment rates (based on historical performance and stress test scenarios). Assumptions used can vary widely from security to security and are influenced by such factors as current debt service coverage ratio, historical prepayment rates, expected prepayment rates, and loans’ current interest rates. The Company then uses, as it deems appropriate, a third party vendor to determine how the underlying collateral cash flows will be distributed to each security. The present value of an impaired debt security results from estimating its future cash flows, discounted at the security’s effective interest rate. The Company expects to recover the remaining noncredit related unrealized losses included as a component of AOCI.
Loans Held for Sale		Loans Held for Sale Loans are transferred into the held for sale classification at the lower of carrying amount or fair value when they are specifically identified for sale and a formal plan exists to sell them.
Loans		Loans Loans represent extensions of credit which the Company has the intent and ability to hold for the foreseeable future or until maturity or payoff. These extensions of credit consist of commercial real estate loans (including land acquisition, development and construction loans), single-family residential loans, commercial loans, loans to financial institutions and acceptances, and consumer loans. Amounts included in the loan portfolio are stated at the amount of unpaid principal, reduced by unamortized net deferred loan fees and origination costs and an allowance for loan losses. Unamortized net deferred loan fees and origination costs amounted to $7.1 million and $7.4 million at December 31, 2018 and 2017, respectively. A loan is placed in nonaccrual status when management believes that collection in full of the principal amount of the loan or related interest is in doubt. Management considers that collectability is in doubt when any of the following factors are present, among others: (1) there is a reasonable probability of inability to collect principal, interest or both, on a loan for which payments are current or delinquent for less than ninety days; or (2) when a required payment of principal, interest or both is delinquent for ninety days or longer, unless the loan is considered well secured and in the process of collection in accordance with regulatory guidelines. Once a loan to a single borrower has been placed in nonaccrual status, management reviews all loans to the same borrower to determine their appropriate accrual status. When a loan is placed in nonaccrual status, accrual of interest and amortization of net deferred loan fees or costs are discontinued, and any accrued interest receivable is reversed against interest income. Payments received on a loan in nonaccrual status are generally applied to its outstanding principal amount, unless there are no doubts on the full collection of the remaining recorded investment in the loan. When there are no doubts on the full collection of the remaining recorded investment in the loan, and there is sufficient documentation to support the collectability of that amount, payments of interest received may be recorded as interest income. A loan in nonaccrual status is returned to accrual status when none of the conditions noted when first placed in nonaccrual status are currently present, none of its principal and interest is past due, and management believes there are reasonable prospects of the loan performing in accordance with its terms. For this purpose, management generally considers there are reasonable prospects of performance in accordance with the loan terms when at least six months of principal and interest payments or principal curtailments have been received, and current financial information of the borrower demonstrates that performance will continue into the near future. The total outstanding principal amount of a loan is reported as past due thirty days following the date of a missed scheduled payment, based on the contractual terms of the loan. Loans which have been modified because the borrowers were experiencing financial difficulty and the Company, for economic or legal reasons related to the debtors’ financial difficulties, granted a concession to the debtors that it would not have otherwise considered, are accounted for as troubled debt restructurings (“TDR”).
Allowance for Loan Losses		Allowance for Loan Losses The allowance for loan losses represents an estimate of the current amount of principal that is probable the Company will be unable to collect given facts and circumstances as of the evaluation date, and includes amounts arising from loans individually and collectively evaluated for impairment. These estimated amounts are recorded through a provision for loan losses charged against income. Management periodically evaluates the adequacy of the allowance for loan losses to maintain it at a level believed reasonable to provide for recognized and unrecognized but inherent losses in the loan portfolio. The Company uses the same methods used to determine the allowance for loan losses, to assess any reserves needed for off-balance sheet credit risks such as unfunded loan commitments and contingent obligations on letters of credit. These reserves for off-balance sheet credit risks are presented in the liabilities section in the consolidated balance sheets. The Company develops and documents its methodology to determine the allowance for loan losses at the portfolio segment level. The Company determines its loan portfolio segments based on the type of loans it carries and their associated risk characteristics. The Company’s loan portfolio segments are: Real Estate, Commercial, Financial Institutions, Consumer and Other. Loans in these portfolio segments have distinguishing borrower needs and differing risks associated with each product type. Real estate loans include commercial loans secured by real estate properties. Commercial loans secured by non-owner occupied real estate properties are generally granted to finance the acquisition or operation of commercial real estate properties, with terms similar to the properties’ useful lives or the operating cycle of the businesses. The main source of repayment of these real estate loans is derived from cash flows or conversion of productive assets and not from the income generated by the disposition of the property held as collateral. The main repayment source of loans granted to finance land acquisition, development and construction projects is generally derived from the disposition of the properties held as collateral, with the repayment capacity of the borrowers and any guarantors considered as alternative sources of repayment. Commercial loans correspond to facilities established for specific business purposes such as financing working capital and capital improvements projects and asset-based lending, among others. These may be loan commitments, uncommitted lines of credit to qualifying customers, short term (one year or less) or longer term credit facilities, and may be secured, unsecured or partially secured. Terms on commercial loans generally do not exceed five years, and exceptions are documented. Commercial loans secured by owner-occupied real estate properties are generally granted to finance the acquisition or operation of commercial real estate properties, with terms similar to the properties’ useful lives or the operating cycle of the businesses. The main source of repayment of these commercial real estate loans is derived from cash flows and not from the income generated by the disposition of the property held as collateral. Commercial loans to borrowers in similar businesses or products with similar characteristics or specific credit requirements are generally evaluated under a standardized commercial credit program. Commercial loans outside the scope of those programs are evaluated on a case by case basis, with consideration of any exposure under an existing commercial credit program. Loans to financial institutions and acceptances are facilities granted to fund certain transactions classified according to their risk level, and primarily include trade financing facilities through letters of credits, bankers’ acceptances, pre- and post-export financing, and working capital loans, among others. Loans in this portfolio segment are generally granted for terms not exceeding three years and on an unsecured basis under the limits of an existing credit program, primarily to large financial institutions in Latin America which the Company believes are of high quality. Prior to approval, management also considers cross-border and portfolio limits set forth in its programs and credit policies. Consumer and other loans are retail open-end and closed-end credits extended to individuals for household, family and other personal expenditures. These loans include loans to individuals secured by their personal residence, including first mortgage, home equity and home improvement loans as well as revolving credit card agreements. Because these loans generally consist of a large number of relatively small-balance, homogeneous loans for each type, their risks are generally evaluated collectively. An individual loan is considered impaired when it is probable that the Company will be unable to collect all amounts due, including both principal and interest, according to the contractual terms of the loan agreement. The Company generally considers as impaired all loans in nonaccrual status, and other loans classified in accordance with an internal risk grading system exceeding a defined threshold when it is probable that an impairment exists and the amount of the potential impairment is reasonably estimable. To determine when it is probable that an impairment exists, the Company considers the extent to which a loan may be inadequately protected by the current net worth and paying capacity of the borrower or any guarantor, or by the current value of the collateral. When a loan is considered impaired, the potential impairment is measured as the excess of the carrying value of the loan over the present value of expected future cash flows at the measurement date, or the fair value of the collateral in the case where the loan is considered collateral-dependent. If the amount of the present value of the loan’s expected future cash flows exceeds the loan’s carrying amount, the loan is still considered impaired but no impairment is recorded. The present value of an impaired loan results from estimating its future cash flows, discounted at the loan’s effective interest rate. In the case of loans considered collateral-dependent, which are generally certain real estate loans for which repayment is expected to be provided solely by the operation or sale of the underlying collateral, the potential impairment is measured based on the fair value of the asset pledged as collateral. The allowance for loan losses on loans considered TDR is generally determined by discounting the restructured cash flows by the original effective interest rate on the loan. Loans that do not meet the criteria of an individually impaired loan are collectively evaluated for impairment. These loans include large groups of smaller homogeneous loan balances, such as loans in the consumer and other loan portfolio segment, and all other loans that have not been individually identified as impaired. This group of collective loans is evaluated for impairment based on measures of historical losses associated with loans within their respective portfolio segments adjusted by a variety of qualitative factors. These qualitative factors incorporate the most recent data reflecting current economic conditions, industry performance trends or obligor concentrations within each portfolio segment, among other factors. Other adjustments may be made to the allowance for loans collectively evaluated for impairment based on any other pertinent information that management considers may affect the estimation of the allowance for loan losses, including a judgmental assessment of internal and external influences on credit quality that are not fully reflected in historical loss or their risk rating data. The measures of historical losses and the related qualitative adjustments are updated quarterly and semi-annually, respectively, to incorporate the most recent loan loss data reflecting current economic conditions. Loans to borrowers that are domiciled in foreign countries, primarily loans in the Consumer and Financial Institutions portfolio segments, are also evaluated for impairment by assessing the probability of additional losses arising from the Company’s exposure to transfer risk. The Company defines transfer risk exposure as the possibility that a loan obligation cannot be serviced in the currency of payment (U.S. Dollars) because the borrower’s country of origin may not have sufficient available currency of payment or may have put restraints on its availability, such as currency controls. To determine an individual country’s transfer risk probability, the Company assigns numerical values corresponding to the perceived performance of that country in certain macroeconomic, social and political factors generally considered in the banking industry for evaluating a country’s transfer risk. A defined country’s transfer risk probability is assigned to that country based on an average of the individual scores given to those factors, calculated using an interpolation formula. The results of this evaluation are also updated semi-annually. Loans in the Real Estate, Commercial and Financial Institutions portfolio segments are charged off against the allowance for loan losses when they are considered uncollectable. These loans are considered uncollectable when a loss becomes evident to management, which generally occurs when the following conditions are present, among others: (1) a loan or portions of a loan are classified as “loss” in accordance with the internal risk grading system; (2) a collection attorney has provided a written statement indicating that a loan or portions of a loan are considered uncollectible; and (3) the carrying value of a collateral-dependent loan exceeds the appraised value of the asset held as collateral. Consumer and other retail loans are charged off against the allowance for loan losses at the earlier of (1) when management becomes aware that a loss has occurred, or (2) when closed-end retail loans become past due 120 days or open-end retail loans become past due 180 days from the contractual due date. For open and closed-end retail loans secured by residential real estate, any outstanding loan balance in excess of the fair value of the property, less cost to sell, is charged off no later than when the loan is 180 days past due from the contractual due date. Consumer and other retail loans may not be charged off when management can clearly document that a past due loan is well secured and in the process of collection such that collection will occur regardless of delinquency status in accordance with regulatory guidelines applicable to these types of loans. Recoveries on loans represent collections received on amounts that were previously charged off against the allowance for loan losses. Recoveries are credited to the allowance for loan losses when received, to the extent of the amount previously charged off against the allowance for loan losses on the related loan. Any amounts collected in excess of this limit are first recognized as interest income, then as a reduction of collection costs, and then as other income.
Transfers of Financial Assets		Transfers of Financial Assets Transfers of financial assets are accounted for as sales or purchases when control over the assets has been surrendered by the transferor. Control over transferred assets is deemed to be surrendered when the assets have been isolated from the transferor, the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and the transferor does not maintain effective control over the transferred assets.
Premises and Equipment, Net		Premises and Equipment, Net Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is computed on the straight-line basis over the estimated useful lives of the related assets. Leasehold improvements are amortized over the remaining term of the lease. Repairs and maintenance are charged to operations as incurred; renewals, betterments and interest during construction are capitalized. Gains or losses on sales of premises and equipment are recorded as other noninterest income or noninterest expense, respectively, at the date of sale. Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. For purposes of recognition and measurement of an impairment loss, when the independent and identifiable cash flow of a single asset may not be determinable, the long-lived asset may be grouped with other assets of like cash flows. Recoverability of an asset or group of assets to be held and used is measured by comparing the carrying amount with future undiscounted net cash flows expected to be generated by the asset or group of assets. If an asset is considered impaired, the impairment recognized is generally measured by the amount by which the carrying amount of the asset or group exceeds its fair value.
Bank Owned Life Insurance		Bank Owned Life Insurance Bank owned life insurance policies (“BOLI”) are recorded at the cash surrender value of the insurance contracts, which represent the amount that may be realizable under the contracts, at the consolidated balance sheet dates. Changes to the cash surrender value are recorded as other noninterest income in the consolidated statements of operations.
Income Taxes		Income Taxes Deferred income tax assets and liabilities are determined using the balance sheet method. Under this method, the resulting net deferred tax asset is determined based on the future tax consequences attributable to differences between the financial statement carrying amount of existing assets and liabilities and their respective tax basis. The effect of changes in tax laws or rates is recognized in results in the period that includes the legislation enactment date. A valuation allowance is established against the deferred tax asset to the extent that management believes that it is more likely than not that any tax benefit will not be realized. Income tax expense is recognized on the periodic change in deferred tax assets and liabilities at the current statutory rates. The results of operations of the Company and the majority of its wholly owned subsidiaries are included in the consolidated federal income tax return of the Company and its subsidiaries as members of the same consolidated tax group. Under the intercompany income tax allocation policy, the Company and the subsidiaries included in the consolidated federal tax group are allocated current and deferred taxes as if they were separate taxpayers. As a result, the subsidiaries included in the consolidated group pay their allocation of income taxes to the Company, or receive payments from the Company to the extent that tax benefits are realized.
Goodwill		Goodwill Goodwill represents the excess of consideration paid over the fair value of the net assets of a savings bank acquired in 2006. Goodwill is not amortized but is reviewed for potential impairment at the reporting unit level on an annual basis in the fourth quarter, or on an interim basis if events or circumstances indicate a potential impairment. As part of its testing, the Company may elect to first assess qualitative factors to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount (“Step 0”). If the results of the Step 0 indicate that more likely than not the reporting unit’s fair value is less than its carrying amount, the Company determines the fair value of the reporting unit relative to its carrying amount, including goodwill (“Step 1”). The Company may also elect to bypass the Step 0 and begin with Step 1. If the fair value of the reporting unit exceeds its carrying amount, goodwill of the reporting unit is considered not impaired. However, if the carrying amount of the reporting unit exceeds its fair value, an additional procedure must be performed (“Step 2”). In Step 2, the implied fair value of the reporting unit’s goodwill is compared to the carrying amount of goodwill allocated to that reporting unit. An impairment loss is recorded to the extent that the carrying amount of goodwill exceeds its implied fair value at the measurement date. At December 31, 2018 and 2017, goodwill was considered not impaired and, therefore, no impairment charges were recorded.
Securities Sold Under Agreements to Repurchase		Securities Sold Under Agreements to Repurchase Securities sold under agreements to repurchase are classified as secured borrowings and are reflected at the amount of cash received in connection with the transaction.
Derivative Instruments		Derivative Instruments Derivative instruments are recognized on the consolidated balance sheet as other assets or other liabilities, at their respective fair values. The accounting for changes in the fair value of a derivative instrument is dependent upon whether the derivative has been designated and qualifies as part of a hedging relationship. For derivative instruments that have not been designated and qualified as hedging relationships, the change in their fair value is recognized in current period earnings. For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative instruments is initially recognized as a component of AOCI, and subsequently reclassified into earnings in the same period during which the hedged transactions affect earnings. The ineffective portion of the gain or loss, if any, is recognized immediately in earnings. The Company has designated certain derivatives as cash flow hedges. Management periodically evaluates the effectiveness of these hedges in offsetting the fluctuations in cash flows due to changes in benchmark interest rates.
Fair Value Measurement	The valuation of securities and derivative instruments is performed through a monthly pricing process using data provided by generally recognized providers of independent data pricing services (the “Pricing Providers”). These Pricing Providers collect, use and incorporate descriptive market data from various sources, quotes and indicators from leading broker dealers to generate independent and objective valuations. The fair value of bank-owned life insurance policies is based on the cash surrender values of the policies as reported by the insurance companies. The valuation techniques and the inputs used in our consolidated financial statements to measure the fair value of our recurring Level 2 financial instruments consider, among other factors, the following: • Similar securities actively traded which are selected from recent market transactions; • Observable market data which includes spreads in relationship to LIBOR, swap curve, and prepayment speed rates, as applicable. • The captured spread and prepayment speed are used to obtain the fair value for each related security. On a quarterly basis, the Company evaluates the reasonableness of the monthly pricing process for the valuation of securities and derivative instruments. This evaluation includes challenging a random sample of the different types of securities in the investment portfolio as of the end of the quarter selected. This challenge consists of obtaining from the Pricing Providers a document explaining the methodology applied to obtain their fair value assessments for each type of investment included in the sample selection. The Company then analyzes in detail the various inputs used in the fair value calculation, both observable and unobservable (e.g., prepayment speeds, yield curve benchmarks, spreads, delinquency rates). Management considers that the consistent application of this methodology allows the Company to understand and evaluate the categorization of its investment portfolio. The methods described above may produce a fair value calculation that may differ from the net realizable value or may not be reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of its financial instruments could result in different estimates of fair value at the reporting date.	Fair Value Measurement Financial instruments are classified based on a three-level valuation hierarchy required by U.S. GAAP. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows: Level 1 Inputs to the valuation methodology are quoted prices in active markets for identical assets or liabilities. Level 1 assets and liabilities may include debt and equity securities that are traded in an active exchange market, as well as certain U.S. securities that are highly liquid and are actively traded in over-the-counter markets. Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets and liabilities. Level 2 assets and liabilities include debt securities with quoted prices that are traded less frequently than exchange traded instruments which value is determined by using a pricing model with inputs that are observable in the market or can be derived principally from, or corroborated by, observable market data. This category generally may include U.S. Government and U.S. Government Sponsored Enterprise mortgage backed debt securities and corporate debt securities. Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Level 3 assets and liabilities may include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation. A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The valuation of securities and derivative instruments is performed through a monthly pricing process using data provided by generally recognized providers of independent data pricing services (the “Pricing Providers”). These Pricing Providers collect, use and incorporate descriptive market data fro m various sources, quotes and indicators from leading broker dealers to generate independent and objective valuations. The fair value of bank-owned life insurance policies is based on the cash surrender values of the policies as reported by the insurance companies. The valuation techniques and the inputs used in our consolidated financial statements to measure the fair value of our recurring Level 2 financial instruments consider, among other factors, the following: • Similar securities actively traded which are selected from recent market transactions; • Observable market data which includes spreads in relationship to LIBOR, swap curve, and prepayment speed rates, as applicable. • The captured spread and prepayment speed is used to obtain the fair value for each related security. On a quarterly basis, the Company evaluates the reasonableness of the monthly pricing process for the valuation of securities and derivative instruments. This evaluation includes challenging a random sample of the different types of securities in the investment portfolio as of the end of the quarter selected. This challenge consists of obtaining from the Pricing Providers a document explaining the methodology applied to obtain their fair value assessments for each type of investment included in the sample selection. The Company then analyzes in detail the various inputs used in the fair value calculation, both observable and unobservable (e.g., prepayment speeds, yield curve benchmarks, spreads, delinquency rates). Management considers that the consistent application of this methodology allows the Company to understand and evaluate the categorization of its investment portfolio. The methods described above may produce a fair value calculation that may differ from the net realizable value or may not be reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of its financial instruments could result in different estimates of fair value at the reporting date.
Recently Issued Accounting Pronouncements		Recently Issued Accounting Pronouncements Emerging Growth Company Section 107 of the JOBS Act provides that, as an “emerging growth company”, or EGC, the Company can take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act for complying with new or revised accounting standards. Therefore, an EGC can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company intends to take advantage of the benefits of this extended transition period, for as long as it is available and consistent with bank regulatory requirements. The Federal bank regulators have not yet recognized or permitted public companies that are EGCs to delay the adoption of accounting pronouncements until those standards would otherwise apply to private companies. The Federal bank regulators position, unless changed, may cause us to adopt accounting principles earlier than required by the SEC. Issued and Adopted Removal of Outdated OCC Guidance In May 2018, the Financial Accounting Standards Board (“FASB”) issued amendments which removed outdated guidance related to the Office of the Comptroller of the Currency (“OCC”)’s Banking Circular 202, Accounting for Net Deferred Tax Changes . This guidance, which limited the net deferred tax debits that can be carried on a bank’s statement of condition for regulatory purposes, has been rescinded by the OCC. These amendments became effective immediately upon issuance and had no impact to the Company’s consolidated financial statements. Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income In February 2018, the FASB issued guidance that allows a reclassification from AOCI to retained earnings for stranded tax effects resulting from the newly enacted federal corporate income tax rate. The amount of the reclassification is the difference between the historical corporate income tax rate and the newly enacted 21% corporate income tax rate pursuant to H.R. 1, An Act to Provide for Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for fiscal year 2018, known as the Tax Cuts and Jobs Act of 2017 (“the 2017 Tax Act”). This guidance is effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted for (1) public business entities for reporting periods for which financial statements have not been issued, and (2) for other entities for reporting periods for which financial statements have not yet been made available for issuance. The Company early-adopted this guidance and reclassified the effect of remeasuring net deferred tax assets related to items within AOCI to retained earnings resulting in a $1.1 million increase in retained earnings in 2017. Issued and Not Yet Adopted New Guidance on Leases In December 2018, the FASB issued amendments to new guidance issued in February 2016 for the recognition and measurement of all leases which has not yet been adopted by the Company. The amendments in this Update address certain lessor’s issues associated with: (i) sales taxes and other similar taxes collected from lessees, (ii) certain lessor costs and, (iii) recognition of variable payments for contracts with lease and nonlease components. The new guidance on leases issued in February 2016 requires lessees to recognize a right-of-use asset and a lease liability for most leases within the scope of the guidance. There were no significant changes to the guidance for lessors. These amendments, and the related pending new guidance, can be adopted using a modified retrospective transition at the beginning of the earliest comparative period presented, and provides for certain practical expedients. The amendments and related new guidance on leases are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020, for private companies, and for fiscal periods beginning after December 15, 2018, and interim periods within those fiscal years, for public companies. Early adoption is permitted. The Company is in the process of gathering a complete inventory of leases and migrating identified lease data onto a new system platform. Based on a preliminary evaluation, the Company expects to recognize an asset and a corresponding lease liability for an amount currently expected to be less than one percent of the Company’s total consolidated assets at adoption. New Guidance on Accounting for Credit Losses on Financial Instruments In November 2018, the FASB issued amendments to pending new guidance on accounting for current expected credit losses on financial instruments (“CECL”) to, among other things, align the implementation date for private companies’ annual financial statements with the implementation date for their interim financial statements. Prior to the issuance of these amendments, the guidance on accounting for CECL was effective for private companies for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. These amendments are effective for fiscal years beginning after December 15, 2021, and interim periods within fiscal to those years, for private companies. In June 2016, the FASB issued the new guidance on CECL. The new guidance introduces an approach based on expected losses to estimate credit losses on various financial instruments, including loans. It also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. The standard is effective for fiscal years beginning after December 15, 2021, and interim periods within fiscal to those years, for private companies, and for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, for public companies. Early adoption is permitted for fiscal years beginning after December 15, 2018. The Company is currently assessing the impact that these changes will have on its consolidated financial statements, when adopted. Changes to the Disclosure Requirements for Fair Value Measurements In August 2018, the FASB issued amendments to the disclosure requirements for fair value measurements. The amendments modify the fair value measurements disclosures with the primary focus to improve effectiveness of disclosures in the notes to the financial statements that is most important to the users. The new guidance modifies the required disclosures related to the valuation techniques and inputs used, uncertainty in measurement, and changes in measurements applied. These amendments are effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Early adoption is permitted. The Company is currently assessing the impact this new guidance may have on the Company’s consolidated financial statements and footnote disclosures. Targeted Improvements to Accounting for Hedging Activities In August 2017, the FASB issued targeted amendments to the guidance for recognition, presentation and disclosure of hedging activities. These targeted amendments expand and refine hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. The amendments also simplify the application of hedge accounting guidance. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years for public business entities. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. The Company is currently evaluating whether the application of this new guidance will have an impact to the Company’s consolidated financial statements. Statement of Cash Flows Classification of Certain Receipts and Payments In August 2016 , the FASB issued specific guidance for the classification of a number of cash receipts and payments, including debt prepayment or debt extinguishment costs, settlement of zero-coupon debt instruments or other debt instruments with coupon interest rates that are insignificant in relation to the effective interest rate of the borrowing, proceeds from the settlement of insurance claims and proceeds from the settlement of BOLI. The new guidance is effective for years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019, for private companies, and for years beginning after December 15, 2017 and interim periods within those fiscal years for public companies. Early adoption is permitted. The Company is currently assessing whether this new guidance will have a material impact on its consolidated statement of cash flows when adopted. Recognition and Measurement of Financial Instruments In January 2016, the FASB issued changes to the guidance on the recognition and measurement of financial instruments. The changes include, among others, the removal of the available-for-sale category for equity securities and updates to certain disclosure requirements. This standard is effective for annual reporting periods beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019, for private companies, and for fiscal periods beginning December 15, 2017, and interim periods within those fiscal years, for public companies, with limited early adoption permitted. As of December 31, 2018, the Company classifies $23.1 million as available for sale equity securities. The Company currently expects that its available for sale equity securities consisting of a mutual fund investment will be reclassified out of the available for sale classification and presented separately on the face of the consolidated balance sheet. At adoption, the Company currently expects the cumulative unrealized loss of these securities previously recognized in AOCL will be recorded as an adjustment to the opening balance of retained earnings. Any further changes to the fair value of equity securities, other than equity method investments, will be recorded in net income. At December 31, 2018, the cumulative unrealized gross loss on this available for sale equity investment was $1.2 million . The Company is currently assessing whether other elements of the new guidance will have a material impact on its consolidated financial position or results of operations or disclosures. Revenue from Contracts with Customers In May 2014, the FASB issued a common revenue standard for recognizing revenue from contracts with customers. This new standard establishes principles for reporting information about the nature, amount, timing, and uncertainty of revenue and cash flows arising from an entity’s contracts with customers. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The amended effective date is annual reporting periods beginning after December 15, 2018, and interim periods beginning after December 15, 2019, for private companies, and for annual reporting periods beginning after December 15, 2017, and interim periods within that reporting period, for public companies. Earlier adoption continues to be permitted. The Company is currently assessing whether the new guidance will have a material impact on its consolidated financial position or results of operations.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The fair value of a financial instrument represents the price that would be received from its sale in an orderly transaction between market participants at the measurement date. The best indication of the fair value of a financial instrument is determined based upon quoted market prices. However, in many cases, there are no quoted market prices for the Company’s various financial instruments. As a result, the Company derives the fair value of the financial instruments held at the reporting period-end, in part, using present value or other valuation techniques. Those techniques are significantly affected by management’s assumptions, the estimated amount and timing of future cash flows and estimated discount rates included in present value and other techniques. The use of different assumptions could significantly affect the estimated fair values of the Company’s financial instruments. Accordingly, the net realized values could be materially different from the estimates presented below. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: • Because of their nature and short-term maturities, the carrying values of the following financial instruments were used as a reasonable estimate of their fair value: cash and cash equivalents, interest earning deposits with banks, variable-rate loans with re-pricing terms shorter than twelve months, demand and savings deposits, short-term time deposits and other borrowings. • The fair value of loans held for sale, securities, bank owned life insurance and derivative instruments, are based on quoted market prices, when available. If quoted market prices are unavailable, fair value is estimated using the pricing process described in Note 17 to the Company’s audited consolidated financial statements on the Form 10-K. • The fair value of commitments and letters of credit is based on the assumption that the Company will be required to perform on all such instruments. The commitment amount approximates estimated fair value. • The fair value of fixed-rate loans, advances from the FHLB, and junior subordinated debentures are estimated using a present value technique by discounting the future expected contractual cash flows using the current rates at which similar instruments would be issued with comparable credit ratings and terms at the measurement date. • The fair value of long-term time deposits, including certificates of deposit, is determined using a present value technique by discounting the future expected contractual cash flows using current rates at which similar instruments would be issued at the measurement date.	The fair value of a financial instrument represents the price that would be received from its sale in an orderly transaction between market participants at the measurement date. The best indication of the fair value of a financial instrument is determined based upon quoted market prices. However, in many cases, there are no quoted market prices for the Company’s various financial instruments. As a result, the Company derives the fair value of the financial instruments held at the reporting period-end, in part, using present value or other valuation techniques. Those techniques are significantly affected by management’s assumptions, the estimated amount and timing of future cash flows and estimated discount rates included in present value and other techniques. The use of different assumptions could significantly affect the estimated fair values of the Company’s financial instruments. Accordingly, the net realized values could be materially different from the estimates presented below. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: • Because of their nature and short-term maturities, the carrying values of the following financial instruments were used as a reasonable estimate of their fair value: cash and cash equivalents, interest earning deposits with banks, variable-rate loans with re-pricing terms shorter than twelve months, demand and savings deposits, short-term time deposits and other borrowings. • The fair value of loans held for sale, securities, bank owned life insurance and derivative instruments, are based on quoted market prices, when available. If quoted market prices are unavailable, fair value is estimated using the pricing process described in Note 17. • The fair value of commitments and letters of credit is based on the assumption that the Company will be required to perform on all such instruments. The commitment amount approximates estimated fair value. • The fair value of fixed-rate loans, advances from the FHLB, and junior subordinated debentures are estimated using a present value technique by discounting the future expected contractual cash flows using the current rates at which similar instruments would be issued with comparable credit ratings and terms at the measurement date. • The fair value of long-term time deposits, including certificates of deposit, is determined using a present value technique by discounting the future expected contractual cash flows using current rates at which similar instruments would be issued at the measurement date.
Segment Reporting	Segment Reporting Prior to the second quarter of 2019, the Company had four reportable segments: Personal and Commercial Banking (“PAC”), Corporate LATAM, Treasury and Institutional. Results of these segments were presented on a managed basis. This structure was driven, among other things, by how the Company previously managed the business, how internal reporting was prepared and analyzed, and how management made decisions. In August 2019, the Company announced that due to changes in the structure of its internal organization that it would report its financial performance as a single operating segment beginning with the quarter ended June 30, 2019. As a result of these changes, all decisions, including those relating to loan growth and concentrations, deposit and other funding, market risk, credit risk, operational risk and pricing are now made after assessing their effects on the Company as a whole, using a single segment concept.

Business, Basis of Presentati_3

Business, Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of the Impact of the Reclassification to the Footnotes of the Company's Consolidated Financial Statements	Segment Reporting Prior to the second quarter of 2019, the Company had four reportable segments: Personal and Commercial Banking (“PAC”), Corporate LATAM, Treasury and Institutional. Results of these segments were presented on a managed basis. This structure was driven, among other things, by how the Company previously managed the business, how internal reporting was prepared and analyzed, and how management made decisions. In August 2019, the Company announced that due to changes in the structure of its internal organization that it would report its financial performance as a single operating segment beginning with the quarter ended June 30, 2019. As a result of these changes, all decisions, including those relating to loan growth and concentrations, deposit and other funding, market risk, credit risk, operational risk and pricing are now made after assessing their effects on the Company as a whole, using a single segment concept. Revisions In 2018, the Company determined to revise its presentation of loans by classes to correct for certain immaterial misclassifications in the presentation of loans by classes in the footnotes to the Company’s unaudited interim consolidated financial statements as of March 31, 2018. The Company assessed the impact of these misclassifications and determined they had no effect on the unaudited interim consolidated balance sheet as of March 31, 2018, the unaudited interim consolidated statements of operations and comprehensive income or the unaudited interim consolidated statement of cash flows for the three months ended March 31, 2018. The following tables show the effects of the correction of the misclassifications to the footnotes to the Company’s unaudited interim consolidated financial statements as of March 31, 2018. This change in classification is reflected in the footnotes to the unaudited interim consolidated financial statements as of March 31, 2019 and for the three months ended March 31, 2019 and 2018. Changes in the allocation of allowance for loan losses and its allocation by impairment methodology and the related investment in loans: As reported: Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 30,246 $ 33,731 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (864 ) 578 (691 ) 977 — Loans charged-off Domestic — (382 ) — (19 ) (401 ) International — — — (400 ) (400 ) Recoveries 34 832 — 53 919 Balances at end of the period $ 29,416 $ 34,759 $ 3,671 $ 4,272 $ 72,118 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,226 $ — $ — $ 2,226 Collectively evaluated 29,416 32,533 3,671 4,272 69,892 $ 29,416 $ 34,759 $ 3,671 $ 4,272 $ 72,118 Investment in loans, net of unearned income Individually evaluated $ 11,238 $ 15,055 $ — $ 342 $ 26,635 Collectively evaluated 2,699,872 2,243,345 416,292 564,306 5,923,815 $ 2,711,110 $ 2,258,400 $ 416,292 $ 564,648 $ 5,950,450 Changes in the allocation of allowance for loan losses and its allocation by impairment methodology and the related investment in loans: As revised: Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (821 ) 535 (691 ) 977 — Loans charged-off Domestic — (382 ) — (19 ) (401 ) International — — — (400 ) (400 ) Recoveries 34 832 — 53 919 Balances at end of the period $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,226 $ — $ — $ 2,226 Collectively evaluated 30,503 31,446 3,671 4,272 69,892 $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Investment in loans, net of unearned income Individually evaluated $ 11,238 $ 15,055 $ — $ 342 $ 26,635 Collectively evaluated 2,803,394 2,139,788 416,292 564,341 5,923,815 $ 2,814,632 $ 2,154,843 $ 416,292 $ 564,683 $ 5,950,450 Changes in the allocation of allowance for loan losses and its allocation by impairment methodology and the related investment in loans: Effects of change: Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 1,044 $ (1,044 ) $ — $ — $ — (Reversal of) provision for loan losses 43 (43 ) — — — Loans charged-off Domestic — — — — — International — — — — — Recoveries — — — — — Balances at end of the period $ 1,087 $ (1,087 ) $ — $ — $ — Allowance for loan losses by impairment methodology Individually evaluated $ — $ — $ — $ — $ — Collectively evaluated 1,087 (1,087 ) — — — $ 1,087 $ (1,087 ) $ — $ — $ — Investment in loans, net of unearned income Individually evaluated $ — $ — $ — $ — $ — Collectively evaluated 103,522 (103,557 ) — 35 — $ 103,522 $ (103,557 ) $ — $ 35 $ —

Securities (Tables)

Securities (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Schedule of available for sale securities from amortized cost to fair value	Amortized cost and approximate fair values of securities available for sale are summarized as follows: March 31, 2019 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 899,571 $ 4,687 $ (13,800 ) $ 890,458 Corporate debt securities 258,421 1,089 (1,168 ) 258,342 U.S. government agency debt securities 218,813 362 (3,839 ) 215,336 Municipal bonds 162,123 2,295 (430 ) 163,988 Mutual funds 24,267 — (800 ) 23,467 Commercial paper — — — — $ 1,563,195 $ 8,433 $ (20,037 ) $ 1,551,591 December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 840,760 $ 2,197 $ (22,178 ) $ 820,779 Corporate debt securities 357,602 139 (5,186 ) 352,555 U.S. government agency debt securities 221,682 187 (4,884 ) 216,985 Municipal bonds 162,438 390 (2,616 ) 160,212 Mutual funds 24,266 — (1,156 ) 23,110 Commercial paper 12,448 — (38 ) 12,410 $ 1,619,196 $ 2,913 $ (36,058 ) $ 1,586,051	Amortized cost and approximate fair values of securities available for sale are summarized as follows: December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 840,760 $ 2,197 $ (22,178 ) $ 820,779 Corporate debt securities 357,602 139 (5,186 ) 352,555 U.S. government agency debt securities 221,682 187 (4,884 ) 216,985 Municipal bonds 162,438 390 (2,616 ) 160,212 Mutual funds 24,266 — (1,156 ) 23,110 Commercial paper 12,448 — (38 ) 12,410 $ 1,619,196 $ 2,913 $ (36,058 ) $ 1,586,051 December 31, 2017 Amortized Gross Unrealized Estimated (in thousands) Gains Losses U.S. government sponsored enterprise debt securities $ 889,396 $ 1,784 $ (15,514 ) $ 875,666 Corporate debt securities 310,781 3,446 (835 ) 313,392 U.S. government agency debt securities 293,908 870 (3,393 ) 291,385 Municipal bonds 179,524 2,343 (1,471 ) 180,396 Mutual funds 24,262 — (645 ) 23,617 U.S. treasury securities 2,700 2 (1 ) 2,701 $ 1,700,571 $ 8,445 $ (21,859 ) $ 1,687,157
Schedule of available for sale securities with unrealized losses	The Company’s securities available for sale with unrealized losses that are deemed temporary, aggregated by the length of time that individual securities have been in a continuous unrealized loss position, are summarized below: March 31, 2019 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 74,413 $ (1,995 ) $ 524,470 $ (11,805 ) $ 598,883 $ (13,800 ) Corporate debt securities 72,106 (365 ) 75,776 (803 ) 147,882 (1,168 ) Municipal bonds — — 48,859 (430 ) 48,859 (430 ) U.S. government agency debt securities 43,198 (436 ) 136,260 (3,403 ) 179,458 (3,839 ) Mutual funds — — 23,220 (800 ) 23,220 (800 ) Commercial paper — — — — — — $ 189,717 $ (2,796 ) $ 808,585 $ (17,241 ) $ 998,302 $ (20,037 ) December 31, 2018 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 90,980 $ (2,995 ) $ 608,486 $ (19,183 ) $ 699,466 $ (22,178 ) Corporate debt securities 243,667 (3,800 ) 75,762 (1,386 ) 319,429 (5,186 ) Municipal bonds 63,580 (939 ) 133,886 (3,945 ) 197,466 (4,884 ) U.S. government agency debt securities 1,449 (6 ) 94,331 (2,610 ) 95,780 (2,616 ) Mutual funds — — 22,865 (1,156 ) 22,865 (1,156 ) Commercial paper 12,410 (38 ) — — 12,410 (38 ) $ 412,086 $ (7,778 ) $ 935,330 $ (28,280 ) $ 1,347,416 $ (36,058 )	The Company’s investment securities available for sale with unrealized losses that are deemed temporary, aggregated by length of time that individual securities have been in a continuous unrealized loss position, are summarized below: December 31, 2018 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 90,980 $ (2,995 ) $ 608,486 $ (19,183 ) $ 699,466 $ (22,178 ) Corporate debt securities 243,667 (3,800 ) 75,762 (1,386 ) 319,429 (5,186 ) U.S. government agency debt securities 63,580 (939 ) 133,886 (3,945 ) 197,466 (4,884 ) Municipal bonds 1,449 (6 ) 94,331 (2,610 ) 95,780 (2,616 ) Mutual funds — — 22,865 (1,156 ) 22,865 (1,156 ) Commercial paper 12,410 (38 ) — — 12,410 (38 ) $ 412,086 $ (7,778 ) $ 935,330 $ (28,280 ) $ 1,347,416 $ (36,058 ) December 31, 2017 Less Than 12 Months 12 Months or More Total (in thousands) Estimated Unrealized Estimated Unrealized Estimated Unrealized U.S. government sponsored enterprise debt securities $ 333,232 $ (2,956 ) $ 485,555 $ (12,558 ) $ 818,787 $ (15,514 ) U.S. government agency debt securities 92,138 (728 ) 128,316 (2,665 ) 220,454 (3,393 ) Municipal bonds 4,895 (8 ) 76,003 (1,463 ) 80,898 (1,471 ) Corporate debt securities 94,486 (751 ) 3,694 (84 ) 98,180 (835 ) Mutual funds — — 23,375 (645 ) 23,375 (645 ) U.S. treasury securities — — 2,199 (1 ) 2,199 (1 ) $ 524,751 $ (4,443 ) $ 719,142 $ (17,416 ) $ 1,243,893 $ (21,859 )
Schedule of held to maturity securities	Amortized cost and approximate fair values of securities held to maturity, are summarized as follows: March 31, 2019 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 81,088 $ 79 $ (1,635 ) $ 79,532 U.S. Government agency debt securities 2,821 22 — 2,843 $ 83,909 $ 101 $ (1,635 ) $ 82,375 December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 82,326 $ — $ (3,889 ) $ 78,437 U.S. Government agency debt securities 2,862 — (49 ) 2,813 $ 85,188 $ — $ (3,938 ) $ 81,250	Amortized cost and approximate fair values of securities held to maturity, are summarized as follows: December 31, 2018 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 82,326 $ — $ (3,889 ) $ 78,437 U.S. Government agency debt securities 2,862 — (49 ) 2,813 $ 85,188 $ — $ (3,938 ) $ 81,250 December 31, 2017 Amortized Gross Unrealized Estimated (in thousands) Gains Losses Securities Held to Maturity - U.S. government sponsored enterprise debt securities $ 86,826 $ 47 $ (441 ) $ 86,432 U.S. Government agency debt securities 3,034 — — 3,034 $ 89,860 $ 47 $ (441 ) $ 89,466
Schedule of contractual maturities of securities	Contractual maturities of securities at March 31, 2019 are as follows: Available for Sale Held to Maturity (in thousands) Amortized Estimated Amortized Estimated Within 1 year $ 34,856 $ 34,769 $ — $ — After 1 year through 5 years 239,679 239,297 — — After 5 years through 10 years 172,190 172,421 — — After 10 years 1,092,203 1,081,637 83,909 82,375 No contractual maturities 24,267 23,467 — — $ 1,563,195 $ 1,551,591 $ 83,909 $ 82,375	Contractual maturities of securities at December 31, 2018 are as follows: Available for Sale Held to Maturity (in thousands) Amortized Estimated Amortized Estimated Within 1 year $ 54,477 $ 54,306 $ — $ — After 1 year through 5 years 330,024 325,752 — — After 5 years through 10 years 166,152 163,039 — — After 10 years 1,044,277 1,019,844 85,188 81,250 No contractual maturities 24,266 23,110 — — $ 1,619,196 $ 1,586,051 $ 85,188 $ 81,250

Loans (Tables)

Loans (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Schedule of loan portfolio by classes and countries	The following tables summarize international loans by country, net of loans fully collateralized with cash of approximately $18.4 million and $19.5 million at March 31, 2019 and December 31, 2018 , respectively. March 31, 2019 (in thousands) Venezuela Others (1) Total Real estate loans Single-family residential (2) $ 124,772 $ 6,525 $ 131,297 Commercial loans — 63,061 63,061 Loans to financial institutions and acceptances — 8,000 8,000 Consumer loans and overdrafts (3) 25,763 8,228 33,991 $ 150,535 $ 85,814 $ 236,349 __________________ (1) Loans to borrowers in fifteen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit to customers with deposits with the Bank. Charging privileges for Venezuela resident card holders are suspended when the cardholders’ average deposits decline below the outstanding credit balance. At the beginning of 2018, the Company changed the monitoring of such balances from quarterly to monthly. The Company determined to discontinue its international credit cards in April 2019. December 31, 2018 (in thousands) Venezuela Others (1) Total Real estate loans Single-family residential (2) $ 128,971 $ 6,467 $ 135,438 Commercial loans — 73,636 73,636 Loans to financial institutions and acceptances — 49,000 49,000 Consumer loans and overdrafts (3) 28,191 13,494 41,685 $ 157,162 $ 142,597 $ 299,759 __________________ (1) Loans to borrowers in seventeen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit to customers with deposits with the Bank. Charging privileges for Venezuela resident card holders are suspended when the cardholders’ average deposits decline below the outstanding credit balance. At the beginning of 2018, the Company changed the monitoring of such balances from quarterly to monthly. The loan portfolio consists of the following loan classes: (in thousands) March 31, December 31, Real estate loans Commercial real estate Nonowner occupied $ 1,852,903 $ 1,809,356 Multi-family residential 878,239 909,439 Land development and construction loans 291,416 326,644 3,022,558 3,045,439 Single-family residential 535,306 533,481 Owner occupied 801,856 777,022 4,359,720 4,355,942 Commercial loans 1,239,525 1,380,428 Loans to financial institutions and acceptances 27,985 68,965 Consumer loans and overdrafts 107,208 114,840 $ 5,734,438 $ 5,920,175	The following tables summarize international loans by country, net of loans fully collateralized with cash of approximately $19.5 million and $31.9 million at December 31, 2018 and 2017 , respectively. December 31, 2018 (in thousands) Venezuela Others (1) Total Real estate loans Single-family residential (2) $ 128,971 $ 6,467 $ 135,438 Loans to financial institutions and acceptances — 49,000 49,000 Commercial loans — 73,636 73,636 Consumer loans and overdrafts (3) 28,191 13,494 41,685 $ 157,162 $ 142,597 $ 299,759 __________________ (1) Loans to borrowers in seventeen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit to customers with deposits with the Bank. Charging privileges for Venezuela residents card holders are suspended when the cardholders’ average deposits decline below the outstanding credit balance. At the beginning of 2018, the Company changed the monitoring of such balances from quarterly to monthly. December 31, 2017 (in thousands) Brazil Venezuela Chile Others (1) Total Real estate loans Single-family residential (2) $ 219 $ 145,069 $ 179 $ 7,246 $ 152,713 Loans to financial institutions and acceptances 129,372 — 93,000 258,811 481,183 Commercial loans 8,451 — — 60,843 69,294 Consumer loans and overdrafts (3) 3,046 37,609 1,364 10,060 52,079 $ 141,088 $ 182,678 $ 94,543 $ 336,960 $ 755,269 __________________ (1) Loans to borrowers in eighteen other countries which do not individually exceed 1% of total assets. (2) Corresponds to mortgage loans secured by single-family residential properties located in the U.S. (3) Mostly comprised of credit card extensions of credit secured to customers with deposits with the Bank. Charging privileges are suspended, if the deposits decline below the outstanding credit balance. The loan portfolio consists of the following loan classes: (in thousands) December 31, December 31, Real estate loans Commercial real estate Nonowner occupied $ 1,809,356 $ 1,713,104 Multi-family residential 909,439 839,709 Land development and construction loans 326,644 406,940 3,045,439 2,959,753 Single-family residential 533,481 512,754 Owner-occupied 777,022 610,386 4,355,942 4,082,893 Commercial loans 1,380,428 1,354,755 Loans to financial institutions and acceptances 68,965 497,626 Consumer loans and overdrafts 114,840 130,951 $ 5,920,175 $ 6,066,225
Schedule of loan portfolio delinquencies	The age analysis of the loan portfolio by class, including nonaccrual loans, as of March 31, 2019 and December 31, 2018 are summarized in the following tables: March 31, 2019 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,852,903 $ 1,852,903 $ — $ — $ — $ — $ — $ — Multi-family residential 878,239 877,574 — 665 — 665 665 — Land development and construction loans 291,416 291,416 — — — — — — 3,022,558 3,021,893 — 665 — 665 665 — Single-family residential 535,306 523,172 7,802 921 3,411 12,134 6,514 — Owner occupied 801,856 799,187 408 1,880 381 2,669 5,192 — 4,359,720 4,344,252 8,210 3,466 3,792 15,468 12,371 — Commercial loans 1,239,525 1,234,890 3,151 399 1,085 4,635 7,361 — Loans to financial institutions and acceptances 27,985 27,985 — — — — — — Consumer loans and overdrafts 107,208 105,434 587 434 753 1,774 37 749 $ 5,734,438 $ 5,712,561 $ 11,948 $ 4,299 $ 5,630 $ 21,877 $ 19,769 $ 749 December 31, 2018 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,809,356 $ 1,809,356 $ — $ — $ — $ — $ — $ — Multi-family residential 909,439 909,439 — — — — — — Land development and construction loans 326,644 326,644 — — — — — — 3,045,439 3,045,439 — — — — — — Single-family residential 533,481 519,730 7,910 2,336 3,505 13,751 6,689 419 Owner occupied 777,022 773,876 2,800 160 186 3,146 4,983 — 4,355,942 4,339,045 10,710 2,496 3,691 16,897 11,672 419 Commercial loans 1,380,428 1,378,022 704 1,062 640 2,406 4,772 — Loans to financial institutions and acceptances 68,965 68,965 — — — — — — Consumer loans and overdrafts 114,840 113,227 474 243 896 1,613 35 884 $ 5,920,175 $ 5,899,259 $ 11,888 $ 3,801 $ 5,227 $ 20,916 $ 16,479 $ 1,303	The age analysis of the loan portfolio by class, including nonaccrual loans, as of December 31, 2018 and 2017 are summarized in the following tables: December 31, 2018 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,809,356 $ 1,809,356 $ — $ — $ — $ — $ — $ — Multi-family residential 909,439 909,439 — — — — — — Land development and construction loans 326,644 326,644 — — — — — — 3,045,439 3,045,439 — — — — — — Single-family residential 533,481 519,730 7,910 2,336 3,505 13,751 6,689 419 Owner-occupied 777,022 773,876 2,800 160 186 3,146 4,983 — 4,355,942 4,339,045 10,710 2,496 3,691 16,897 11,672 419 Commercial loans 1,380,428 1,378,022 704 1,062 640 2,406 4,772 — Loans to financial institutions and acceptances 68,965 68,965 — — — — — — Consumer loans and overdrafts 114,840 113,227 474 243 896 1,613 35 884 $ 5,920,175 $ 5,899,259 $ 11,888 $ 3,801 $ 5,227 $ 20,916 $ 16,479 $ 1,303 December 31, 2017 Total Loans, Past Due Total Loans in Total Loans (in thousands) Current 30-59 60-89 Greater than Total Past Real estate loans Commercial real estate Nonowner occupied $ 1,713,104 $ 1,712,624 $ — $ — $ 480 $ 480 $ 489 $ — Multi-family residential 839,709 839,709 — — — — — — Land development and construction loans 406,940 406,940 — — — — — — 2,959,753 2,959,273 — — 480 480 489 — Single-family residential 512,754 501,393 6,609 2,750 2,002 11,361 5,004 226 Owner-occupied 610,386 602,643 3,000 174 4,569 7,743 12,227 — 4,082,893 4,063,309 9,609 2,924 7,051 19,584 17,720 226 Commercial loans 1,354,755 1,350,667 385 5 3,698 4,088 8,947 — Loans to financial institutions and acceptances 497,626 497,626 — — — — — — Consumer loans and overdrafts 130,951 130,846 57 29 19 105 55 — $ 6,066,225 $ 6,042,448 $ 10,051 $ 2,958 $ 10,768 $ 23,777 $ 26,722 $ 226

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Schedule of allowance for loan losses	The following is a summary of the recorded investment amount of loan sales by portfolio segment: Three Months Ended March 31, Real Estate Commercial Financial Consumer Total 2019 $ 23,475 $ 126,838 $ — $ 1,864 $ 152,177 2018 $ 2,958 $ 10,000 $ — $ — $ 12,958 The analyses by loan segment of the changes in the allowance for loan losses for the three months ended March 31, 2019 and 2018 , and its allocation by impairment methodology and the related investment in loans, net as of March 31, 2019 and 2018 are summarized in the following tables: Three Months Ended March 31, 2019 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 22,778 $ 30,018 $ 445 $ 8,521 $ 61,762 (Reversal of) provision for loan losses (322 ) (31 ) (339 ) 692 — Loans charged-off Domestic — (992 ) — (196 ) (1,188 ) International — (18 ) — (406 ) (424 ) Recoveries — 123 — 49 172 Balances at end of the period $ 22,456 $ 29,100 $ 106 $ 8,660 $ 60,322 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 1,593 $ — $ 1,202 $ 2,795 Collectively evaluated 22,456 27,507 106 7,458 57,527 $ 22,456 $ 29,100 $ 106 $ 8,660 $ 60,322 Investment in loans, net of unearned income Individually evaluated $ 711 $ 12,325 $ — $ 3,392 $ 16,428 Collectively evaluated 3,016,569 2,137,165 27,985 536,291 5,718,010 $ 3,017,280 $ 2,149,490 $ 27,985 $ 539,683 $ 5,734,438 Three Months Ended March 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the period $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (821 ) 535 (691 ) 977 — Loans charged-off Domestic — (382 ) — (19 ) (401 ) International — — — (400 ) (400 ) Recoveries 34 832 — 53 919 Balances at end of the period $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,226 $ — $ — $ 2,226 Collectively evaluated 30,503 31,446 3,671 4,272 69,892 $ 30,503 $ 33,672 $ 3,671 $ 4,272 $ 72,118 Investment in loans, net of unearned income Individually evaluated $ 11,238 $ 15,055 $ — $ 342 $ 26,635 Collectively evaluated 2,803,394 2,139,788 416,292 564,341 5,923,815 $ 2,814,632 $ 2,154,843 $ 416,292 $ 564,683 $ 5,950,450	The analyses by loan segment of the changes in the allowance for loan losses for the years ended December 31, 2018 , 2017 and 2016 and its allocation by impairment methodology and the related investment in loans, net as of December 31, 2018 , 2017 and 2016 are summarized in the following tables: December 31, 2018 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the year $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 (Reversal of) provision for loan losses (2,885 ) 1,099 (3,917 ) 6,078 375 Loans charged-off Domestic (5,839 ) (3,662 ) — (194 ) (9,695 ) International — (1,473 ) — (1,392 ) (2,865 ) Recoveries 212 1,367 — 368 1,947 Balances at end of the year $ 22,778 $ 30,018 $ 445 $ 8,521 $ 61,762 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 1,282 $ — $ 1,091 $ 2,373 Collectively evaluated 22,778 28,736 445 7,430 59,389 $ 22,778 $ 30,018 $ 445 $ 8,521 $ 61,762 Investment in loans, net of unearned income Individually evaluated $ 717 $ 9,652 $ — $ 3,089 $ 13,458 Collectively evaluated 3,037,604 2,254,607 69,003 545,503 5,906,717 $ 3,038,321 $ 2,264,259 $ 69,003 $ 548,592 $ 5,920,175 December 31, 2017 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the year $ 30,713 $ 40,897 $ 5,304 $ 4,837 $ 81,751 Reversal of provision for loan losses (221 ) (1,027 ) (942 ) (1,300 ) (3,490 ) Loans charged-off Domestic (97 ) (1,979 ) — (424 ) (2,500 ) International — (6,166 ) — (757 ) (6,923 ) Recoveries 895 962 — 1,305 3,162 Balances at end of the year $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 2,866 $ — $ — $ 2,866 Collectively evaluated 31,290 29,821 4,362 3,661 69,134 $ 31,290 $ 32,687 $ 4,362 $ 3,661 $ 72,000 Investment in loans, net of unearned income Individually evaluated $ 1,318 $ 20,907 $ — $ 374 $ 22,599 Collectively evaluated 2,912,786 2,073,351 497,626 559,863 6,043,626 $ 2,914,104 $ 2,094,258 $ 497,626 $ 560,237 $ 6,066,225 December 31, 2016 (in thousands) Real Estate Commercial Financial Consumer Total Balances at beginning of the year $ 18,331 $ 44,734 $ 9,226 $ 4,752 $ 77,043 Provision for (reversal of) loan losses 8,570 16,153 (3,922 ) 1,309 22,110 Loans charged-off Domestic (94 ) (1,496 ) — (224 ) (1,814 ) International — (19,610 ) — (1,186 ) (20,796 ) Recoveries 3,906 1,116 — 186 5,208 Balances at end of the year $ 30,713 $ 40,897 $ 5,304 $ 4,837 $ 81,751 Allowance for loan losses by impairment methodology Individually evaluated $ — $ 6,596 $ — $ — $ 6,596 Collectively evaluated 30,713 34,301 5,304 4,837 75,155 $ 30,713 $ 40,897 $ 5,304 $ 4,837 $ 81,751 Investment in loans, net of unearned income Individually evaluated $ 13,792 $ 51,332 $ — $ 4,205 $ 69,329 Collectively evaluated 2,364,161 2,398,552 416,336 516,383 5,695,432 $ 2,377,953 $ 2,449,884 $ 416,336 $ 520,588 $ 5,764,761 The following is a summary of the recorded investment amount of loan sales by portfolio segment in the years ended December 2018, 2017 and 2016: (in thousands) Real Estate Commercial Financial Consumer Total 2018 $ 20,248 $ 138,244 $ — $ 14,981 $ 173,473 2017 $ 15,040 $ 35,260 $ 40,177 $ — $ 90,477 2016 $ 9,151 $ 72,597 $ 23,500 $ — $ 105,248
Schedule of impaired loans	The following is a summary of impaired loans as of March 31, 2019 and December 31, 2018 March 31, 2019 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average (1) Total Unpaid Principal Balance Valuation Allowance Real estate loans Commercial real estate Nonowner occupied $ — $ — $ — $ 5,188 $ — $ — Multi-family residential — 711 711 719 716 — Land development and construction — — — — — — — 711 711 5,907 716 — Single-family residential 3,411 289 3,700 4,182 3,802 1,346 Owner occupied 363 4,352 4,715 5,187 4,715 159 3,774 5,352 9,126 15,276 9,233 1,505 Commercial loans 7,169 120 7,289 7,178 8,427 1,289 Consumer loans and overdrafts 2 11 13 17 11 1 $ 10,945 $ 5,483 $ 16,428 $ 22,471 $ 17,671 $ 2,795 December 31, 2018 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average (1) Total Unpaid Principal Balance Valuation Allowance Real estate loans Commercial real estate Nonowner occupied $ — $ — $ — $ 7,935 $ — $ — Multi-family residential — 717 717 724 722 — Land development and construction loans — — — — — — — 717 717 8,659 722 — Single-family residential 3,086 306 3,392 4,046 3,427 1,235 Owner occupied 169 4,427 4,596 5,524 4,601 75 3,255 5,450 8,705 18,229 8,750 1,310 Commercial loans 4,585 148 4,733 7,464 6,009 1,059 Consumer loans and overdrafts 9 11 20 15 17 4 $ 7,849 $ 5,609 $ 13,458 $ 25,708 $ 14,776 $ 2,373 _______________ (1) Average using trailing four quarter balances.	The following is a summary of impaired loans as of December 31, 2018 and 2017 : December 31, 2018 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average Total Unpaid Principal Balance Valuation Allowance Interest Income Recognized Real estate loans Commercial real estate Nonowner occupied $ — $ — $ — $ 7,935 $ — $ — — Multi-family residential — 717 717 724 722 — 32 Land development and construction — — — — — — — — 717 717 8,659 722 — 32 Single-family residential 3,086 306 3,392 4,046 3,427 1,235 108 Owner-occupied 169 4,427 4,596 5,524 4,601 75 14 3,255 5,450 8,705 18,229 8,750 1,310 154 Commercial loans 4,585 148 4,733 7,464 6,009 1,059 952 Consumer loans and overdrafts 9 11 20 15 17 4 — $ 7,849 $ 5,609 $ 13,458 $ 25,708 $ 14,776 $ 2,373 $ 1,106 December 31, 2017 Recorded Investment (in thousands) With a Valuation Allowance Without a Valuation Allowance Total Year Average Total Unpaid Principal Balance Valuation Allowance Interest Income Recognized Real estate loans Commercial real estate Nonowner occupied $ — $ 327 $ 327 $ 225 $ 327 $ — $ — Multi-family residential — 1,318 1,318 7,898 1,330 — 54 Land development and construction loans — — — 1,359 — — — — 1,645 1,645 9,482 1,657 — 54 Single-family residential — 877 877 3,100 871 — 1,101 Owner-occupied — 10,918 10,918 13,440 12,323 — 11 — 13,440 13,440 26,022 14,851 — 1,166 Commercial loans 7,173 1,986 9,159 18,211 14,784 2,866 12 Consumer loans and overdrafts — — — — — — — $ 7,173 $ 15,426 $ 22,599 $ 44,233 $ 29,635 $ 2,866 $ 1,178
Schedule of Troubled Debt Restructurings		The following table shows information about loans that were modified and met the definition of TDR during 2018, 2017 and 2016: 2018 2017 2016 (in thousands) Number of Contracts Recorded Investment Number of Contracts Recorded Investment Number of Contracts Recorded Investment Real estate loans Commercial real estate Nonowner occupied (1) 1 $ — — $ — 1 $ 208 Single-family residential — — 2 — 1 49 Owner-occupied 1 1,831 1 — 3 846 2 1,831 3 — 5 1,103 Commercial loans 2 622 1 1,473 2 11,172 Consumer loans and overdrafts 1 10 — — — — Total (2) (3) 5 $ 2,463 4 $ 1,473 7 $ 12,275 _________________ (1) In the fourth quarter of 2018, the Company sold one non-performing loan in the Houston area with a carrying value of $10.2 million , and charged off $5.8 million against the allowance for loan losses. This loan had been modified and met the definition of a TDR during the second quarter of 2018. (2) During 2018 and 2017, the Company charged off a total of approximately $6.9 million and $6.0 million , respectively, against the allowance for loan losses as a result of these TDR loans. (3) At December 31, 2018, 2017 and 2016, all TDR loans were primarily real estate and commercial loans under modified terms, including interest payment deferments and others, that did not substantially impact the allowance for loan losses since the recorded investment in these impaired loans corresponded to their realizable value, which approximated their fair values, or higher, prior to their designation as TDR. During 2018, 2017 and 2016, TDR loans that subsequently defaulted within the 12 months of restructuring were as follows: 2018 2017 2016 (in thousands) Number of Contracts Recorded Investment Number of Contracts Recorded Investment Number of Contracts Recorded Investment Real estate loans Single-family residential — $ — — $ — 6 $ 3,010 Owner-occupied 1 1,831 1 618 4 2,959 1 1,831 1 618 10 5,969 Commercial loans 1 589 — — — — Consumer loans and overdrafts 1 10 — — — — 3 $ 2,430 1 $ 618 10 $ 5,969
Schedule of credit quality indicators	The Company’s investment in loans by credit quality indicators as of March 31, 2019 and December 31, 2018 are summarized in the following tables: March 31, 2019 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,844,618 $ 8,285 $ — $ — $ — $ 1,852,903 Multi-family residential 877,574 665 — — 878,239 Land development and construction loans 291,416 — — — — 291,416 3,013,608 8,285 665 — — 3,022,558 Single-family residential 528,792 — 6,514 — — 535,306 Owner occupied 780,457 12,767 8,632 — — 801,856 4,322,857 21,052 15,811 — — 4,359,720 Commercial loans 1,225,901 3,992 9,073 559 — 1,239,525 Loans to financial institutions and acceptances 27,985 — — — — 27,985 Consumer loans and overdrafts 101,264 — 5,944 — — 107,208 $ 5,678,007 $ 25,044 $ 30,828 $ 559 $ — $ 5,734,438 December 31, 2018 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,802,573 $ 6,561 $ 222 $ — $ — $ 1,809,356 Multi-family residential 909,439 — — — — 909,439 Land development and construction loans 326,644 — — — — 326,644 3,038,656 6,561 222 — — 3,045,439 Single-family residential 526,373 — 7,108 — — 533,481 Owner occupied 758,552 9,019 9,451 — — 777,022 4,323,581 15,580 16,781 — — 4,355,942 Commercial loans 1,369,434 3,943 6,462 589 — 1,380,428 Loans to financial institutions and acceptances 68,965 — — — — 68,965 Consumer loans and overdrafts 108,778 — 6,062 — — 114,840 $ 5,870,758 $ 19,523 $ 29,305 $ 589 $ — $ 5,920,175	The Company’s loans by credit quality indicators as of December 31, 2018 and 2017 are summarized in the following tables: December 31, 2018 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,802,573 $ 6,561 $ 222 $ — $ — $ 1,809,356 Multi-family residential 909,439 — — — — 909,439 Land development and construction loans 326,644 — — — — 326,644 3,038,656 6,561 222 — — 3,045,439 Single-family residential 526,373 — 7,108 — — 533,481 Owner-occupied 758,552 9,019 9,451 — — 777,022 4,323,581 15,580 16,781 — — 4,355,942 Commercial loans 1,369,434 3,943 6,462 589 — 1,380,428 Loans to financial institutions and acceptances 68,965 — — — — 68,965 Consumer loans and overdrafts 108,778 — 6,062 — — 114,840 $ 5,870,758 $ 19,523 $ 29,305 $ 589 $ — $ 5,920,175 December 31, 2017 Credit Risk Rating Nonclassified Classified (in thousands) Pass Special Mention Substandard Doubtful Loss Total Real estate loans Commercial real estate Nonowner occupied $ 1,711,595 $ 1,020 $ 489 $ — $ — $ 1,713,104 Multi-family residential 839,709 — — — — 839,709 Land development and construction loans 406,940 — — — — 406,940 2,958,244 1,020 489 — — 2,959,753 Single-family residential 506,885 — 5,869 — — 512,754 Owner-occupied 592,468 4,051 13,867 — — 610,386 4,057,597 5,071 20,225 — — 4,082,893 Commercial loans 1,334,543 6,100 14,112 — — 1,354,755 Loans to financial institutions and acceptances 497,626 — — — — 497,626 Consumer loans and overdrafts 126,838 — 4,113 — — 130,951 $ 6,016,604 $ 11,171 $ 38,450 $ — $ — $ 6,066,225 The following is a summary of the master risk categories and their associated loan risk ratings, as well as a description of the general characteristics of the master risk category: Loan Risk Rating Master risk category Nonclassified 4 to 10 Classified 1 to 3 Substandard 3 Doubtful 2 Loss 1
Schedule of financing receivables, non accrual status		Single-family residential loans: December 31, (in thousands, except percentages) 2018 2017 2016 Loan Balance % Loan Balance % Loan Balance % Accrual Loans Current $ 518,106 97.12 % $ 499,307 97.38 % $ 455,410 96.80 % 30-59 Days Past Due 7,634 1.43 % 6,025 1.17 % 4,675 0.99 % 60-89 Days Past Due 633 0.12 % 2,193 0.43 % 1,395 0.30 % 90+ Days Past Due 419 0.08 % 225 0.04 % 116 0.02 % 8,686 1.63 % 8,443 1.64 % 6,186 1.31 % Total Accrual Loans $ 526,792 98.75 % $ 507,750 99.02 % $ 461,596 98.11 % Non-Accrual Loans Current $ 1,624 0.30 % $ 2,086 0.41 % $ 2,290 0.49 % 30-59 Days Past Due 276 0.05 % 584 0.11 % — — % 60-89 Days Past Due 1,703 0.32 % 557 0.11 % 38 0.01 % 90+ Days Past Due 3,086 0.58 % 1,777 0.35 % 6,565 1.39 % 5,065 0.95 % 2,918 0.57 % 6,603 1.40 % Total Non-Accrual Loans 6,689 1.25 % 5,004 0.98 % 8,893 1.89 % $ 533,481 100.00 % $ 512,754 100.00 % $ 470,489 100.00 % Consumer loans and overdrafts: December 31, (in thousands, except percentages) 2018 2017 2016 Loan Balance % Loan Balance % Loan Balance % Accrual Loans Current $ 113,211 98.58 % $ 130,830 99.91 % $ 120,463 98.40 % 30-59 Days Past Due 466 0.41 % 48 0.04 % 1,076 0.88 % 60-89 Days Past Due 243 0.21 % 18 0.01 % 443 0.36 % 90+ Days Past Due 885 0.77 % — — % 370 0.30 % 1,594 1.39 % 66 0.05 % 1,889 1.54 % Total Accrual Loans $ 114,805 99.97 % $ 130,896 99.96 % $ 122,352 99.94 % Non-Accrual Loans Current $ 16 0.01 % $ 16 0.01 % $ 43 0.03 % 30-59 Days Past Due 8 0.01 % 9 0.01 % 22 0.02 % 60-89 Days Past Due — — % 11 0.01 % — — % 90+ Days Past Due 11 0.01 % 19 0.01 % 9 0.01 % 19 0.02 % 39 0.03 % 31 0.03 % Total Non-Accrual Loans 35 0.03 % 55 0.04 % 74 0.06 % $ 114,840 100.00 % $ 130,951 100.00 % $ 122,426 100.00 %

Premises and Equipment, Net Pre

Premises and Equipment, Net Premises and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule of Premises and Equipment	Premises and equipment, net include the following: December 31, Estimated (in thousands) 2018 2017 (in years) Land $ 18,307 $ 18,307 NA Buildings and improvements 100,152 93,848 10–30 Equipment leased under an operating lease — 19,626 15 Furniture and equipment 21,579 19,832 3–10 Computer equipment and software 31,225 29,749 3 Leasehold improvements 19,301 18,260 5–10 Work in progress 5,170 6,532 NA $ 195,734 $ 206,154 Less: Accumulated depreciation and amortization (72,231 ) (76,797 ) $ 123,503 $ 129,357

Time Deposits (Tables)

Time Deposits (Tables)	12 Months Ended
	Dec. 31, 2018
Banking and Thrift [Abstract]
Schedule of Time Deposit Maturities	At December 31, 2018 and 2017 time deposits maturities were as follows: (in thousands, except percentages) 2018 2017 Year of Maturity Amount % Amount % 2018 $ — — % $ 1,357,668 60.44 % 2019 1,438,565 60.26 % 331,515 14.76 % 2020 361,255 15.13 % 194,175 8.64 % 2021 168,850 7.07 % 103,781 4.62 % 2022 135,265 5.67 % 106,550 4.74 % 2023 and thereafter 283,196 11.87 % 152,745 6.80 % Total $ 2,387,131 100.00 % $ 2,246,434 100.00 %

Advances From the Federal Hom_2

Advances From the Federal Home Loan Bank and Other Borrowings (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Banking and Thrift [Abstract]
Schedule of outstanding advances from the FHLB	The Company had outstanding advances from the FHLB and other borrowings. These borrowings bear fixed interest rates or variable rates based on 3-month LIBOR as follows: Year of Maturity Interest March 31, 2019 December 31, 2018 (in thousands, except percentages) 2019 1.80% to 3.86% $ 385,000 $ 440,000 2020 1.50% to 2.74% 265,000 306,000 2021 1.93% to 3.08% 210,000 210,000 2022 2.48% to 2.80% 120,000 120,000 2023 and after 2.95% to 3.23% 90,000 90,000 $ 1,070,000 $ 1,166,000	At December 31, 2018 and 2017, the Company had outstanding advances from the FHLB and other borrowings as follows: Year of Maturity Interest December 31, 2018 December 31, 2017 (in thousands, except percentages) 2018 0.90% to 2.03% $ — $ 567,000 2019 1.00% to 3.86% 440,000 155,000 2020 1.50% to 2.74% 306,000 211,000 2021 1.93% to 3.08% 210,000 240,000 2022 and after 2.48% to 3.23% 210,000 — $ 1,166,000 $ 1,173,000

Derivative Instruments (Tables)

Derivative Instruments (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	At March 31, 2019 and December 31, 2018 , the fair values of the Company’s derivative instruments were as follows: March 31, 2019 December 31, 2018 (in thousands) Other Assets Other Liabilities Other Assets Other Liabilities Interest rate swaps designated as cash flow hedges $ — $ — $ 9,386 $ 283 Interest rate swaps not designated as hedging instruments: Customers 4,815 — 1,420 — Third party broker — 4,815 — 1,420 4,815 4,815 1,420 1,420 Interest rate caps not designated as hedging instruments: Customers — 176 — 685 Third party broker 176 — 685 — 176 176 685 685 $ 4,991 $ 4,991 $ 11,491 $ 2,388	At December 31, 2018 and 2017 the fair value of the Company’s derivative instruments was as follows: December 31, 2018 December 31, 2017 (in thousands) Other Assets Other Liabilities Other Assets Other Liabilities Interest rate swaps designated as cash flow hedges $ 9,386 $ 283 $ 5,462 $ — Interest rate swaps not designated as hedging instruments: Customers 1,420 — 1,375 — Third party broker — 1,420 — 1,375 1,420 1,420 1,375 1,375 Interest rate caps not designated as hedging instruments: Customers — 685 — 195 Third party broker 685 — 195 — 685 685 195 195 $ 11,491 $ 2,388 $ 7,032 $ 1,570

Junior Subordinated Debenture_2

Junior Subordinated Debentures Held by Trust Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Summary of the Outstanding Trust Preferred Securities	The following table provides information of the outstanding Trust Preferred Securities issued by, and the junior subordinated debentures issued to, each of the Trust Subsidiaries as of December 31, 2018 and 2017: (in thousands) Amount of Principal Year of Annual Rate of Trust Year of Commercebank Capital Trust I $ 26,830 $ 28,068 1998 8.90% 2028 Commercebank Statutory Trust II 15,000 15,464 2000 10.60% 2030 Commercebank Capital Trust III 10,000 10,400 2001 10.18% 2031 Commercebank Capital Trust VI 9,250 9,537 2002 3-M LIBOR + 3.35% 2033 Commercebank Capital Trust VII 8,000 8,248 2003 3-M LIBOR + 3.25% 2033 Commercebank Capital Trust VIII 5,000 5,155 2004 3-M LIBOR + 2.85% 2034 Commercebank Capital Trust IX 25,000 25,774 2006 3-M LIBOR + 1.75% 2038 Commercebank Capital Trust X 15,000 15,464 2006 3-M LIBOR + 1.78% 2036 $ 114,080 $ 118,110

Income Taxes Income Tax (Tables

Income Taxes Income Tax (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The components of the income tax expense for the years ended December 31, 2018, 2017 and 2016 are as follows: (in thousands) 2018 2017 2016 Current provision Federal $ 7,298 $ 19,194 $ 10,981 State 1,964 1,763 844 Impact of lower rate under the 2017 Tax Act - Remeasurement of net deferred tax assets, other than balances corresponding to items in AOCI — 8,470 — Remeasurement of net deferred tax assets corresponding to items in AOCI — 1,094 — Deferred tax expense (benefit) 2,471 3,471 (1,614 ) $ 11,733 $ 33,992 $ 10,211
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the income tax expense at the statutory federal income tax rate to the Company’s effective income tax rate for the years ended December 31, 2018, 2017, and 2016 follows: 2018 2017 2016 (in thousands) Amount % Amount % Amount % Tax expense calculated at the statutory federal income tax rate $ 12,089 21.00 % $ 26,967 35.00 % $ 11,827 35.00 % Increases (decreases) resulting from: Impact of the 2017 Tax Act - Remeasurement of net deferred tax assets — — % 9,564 12.41 % — — % Non-taxable interest income (1,507 ) (2.62 )% (1,643 ) (2.13 )% (1,132 ) (3.35 )% Non-taxable BOLI income (1,223 ) (2.12 )% (1,910 ) (2.48 )% (1,547 ) (4.58 )% Non-deductible Spin-off costs 1,711 2.97 % — — % — — % Disallowed interest expense allocable to tax exempt securities and other expenses 627 1.09 % 577 0.75 % 464 1.37 % State and city income taxes, net of federal income tax benefit (131 ) (0.23 )% 1,146 1.49 % 549 1.62 % Other, net 167 0.29 % (709 ) (0.92 )% 50 0.16 % $ 11,733 20.38 % $ 33,992 44.12 % $ 10,211 30.22 %
Schedule of Deferred Tax Assets	The composition of the net deferred tax asset is as follows: December 31, (in thousands) 2018 2017 Tax effect of temporary differences Provision for loan losses $ 13,581 $ 13,372 Net unrealized losses in other comprehensive income 5,878 1,680 Deferred compensation expense 3,489 3,460 Dividend income 605 946 Interest income on nonaccrual loans 341 599 Goodwill amortization (3,979 ) (3,223 ) Depreciation and amortization (3,934 ) (3,601 ) Other 329 1,350 Net deferred tax assets $ 16,310 $ 14,583

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (“AOCL”) (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Components of AOCL	The components of AOCL are summarized as follows using applicable blended average federal and state tax rates for each period: March 31, 2019 December 31, 2018 (in thousands) Before Tax Tax Net of Tax Before Tax Tax Net of Tax Unrealized losses on available for sale securities $ (11,604 ) $ 2,838 $ (8,766 ) $ (33,145 ) $ 8,104 $ (25,041 ) Unrealized gains on interest rate swaps designated as cash flow hedges 8,759 (2,142 ) $ 6,617 9,103 (2,226 ) $ 6,877 Total AOCL $ (2,845 ) $ 696 $ (2,149 ) $ (24,042 ) $ 5,878 $ (18,164 )	The components of AOCL are summarized as follows using applicable blended average federal and state tax rates for each period: December 31, 2018 December 31, 2017 (in thousands) Before Tax Tax Net of Tax Before Tax Tax Net of Tax Unrealized losses on available for sale securities $ (33,145 ) $ 8,104 $ (25,041 ) $ (13,414 ) $ 2,883 $ (10,531 ) Unrealized gains on interest rate swaps designated as cash flow hedges 9,103 (2,226 ) $ 6,877 5,602 (1,204 ) 4,398 Total AOCL $ (24,042 ) $ 5,878 $ (18,164 ) $ (7,812 ) $ 1,679 $ (6,133 )
Components of Other Comprehensive Loss	The components of other comprehensive income (loss) for the periods presented are summarized as follows: Three Months Ended March 31, 2019 2018 (in thousands) Before Tax Tax Net of Tax Before Tax Tax Net of Tax Unrealized gains (losses) on available for sale securities: Change in fair value arising during the period $ 21,545 $ (5,267 ) $ 16,278 $ (20,850 ) $ 5,873 $ (14,977 ) Reclassification adjustment for net gains included in net income (4 ) 1 (3 ) — — — 21,541 (5,266 ) 16,275 (20,850 ) 5,873 (14,977 ) Unrealized (losses) gains on interest rate swaps designated as cash flow hedges: Change in fair value arising during the period (15 ) 4 (11 ) 6,101 (1,821 ) 4,280 Reclassification adjustment for net interest (income) expense included in net income (329 ) 80 (249 ) 121 (31 ) 90 (344 ) 84 (260 ) 6,222 (1,852 ) 4,370 Total other comprehensive income (loss) $ 21,197 $ (5,182 ) $ 16,015 $ (14,628 ) $ 4,021 $ (10,607 )	The components of other comprehensive income (loss) for the three-year period ended December 31, 2018 is summarized as follows: December 31, 2018 (in thousands) Before Tax Tax Net of Tax Unrealized losses on available for sale securities: Change in fair value arising during the period $ (20,730 ) $ 5,465 $ (15,265 ) Reclassification adjustment for net losses included in net income 999 (244 ) 755 (19,731 ) 5,221 (14,510 ) Unrealized gains on interest rate swaps designated as cash flow hedges: Change in fair value arising during the period 3,744 (1,081 ) 2,663 Reclassification adjustment for net interest income included in net income (243 ) 59 (184 ) 3,501 (1,022 ) 2,479 Total other comprehensive loss $ (16,230 ) $ 4,199 $ (12,031 ) December 31, 2017 (in thousands) Before Tax Tax Net of Tax Unrealized gains on available for sale securities arising during the period $ 6,875 $ (3,298 ) $ 3,577 Reclassification adjustment for net losses on sale of securities included in net income 1,601 (768 ) 833 Unrealized gains on interest rate swaps designated as cash flow hedges 293 (141 ) 152 Total other comprehensive income $ 8,769 $ (4,207 ) $ 4,562 December 31, 2016 (in thousands) Before Tax Tax Net of Tax Unrealized losses on available for sale securities arising during the period $ (5,952 ) $ 2,113 $ (3,839 ) Reclassification adjustment for net gains on sale of securities included in net income (1,556 ) 552 (1,004 ) Unrealized gains on interest rate swaps designated as cash flow hedges 5,578 (1,980 ) 3,598 Total other comprehensive loss $ (1,930 ) $ 685 $ (1,245 )

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Summary of Related Party Amounts Included in the Consolidated Balance Sheets and the Consolidated Statements of Operations	In addition to loans to related parties and associated interest income, which are described below, included in the consolidated balance sheets and the consolidated statements of operations are amounts with related parties as follows: December 31, (in thousands) 2018 2017 Liabilities Demand deposits, noninterest bearing $ 9,447 $ 24,879 Demand deposits, interest bearing 3,721 21,071 Money market 308 449 Time deposits and accounts payable 1,350 7,636 Total due to related parties $ 14,826 $ 54,035 Years Ended December 31, (in thousands) 2018 2017 2016 Income Data processing and other services $ 2,168 $ 1,532 $ 2,328 Rental income from operating lease 248 1,971 1,976 Service charges 95 90 83 $ 2,511 $ 3,593 $ 4,387 Expenses Interest expense $ 126 $ 85 $ 73 Loss on sale of securities — — 796 Fees and other expenses 623 302 504 749 387 1,373 $ 1,762 $ 3,206 $ 3,014

Stockholders_ Equity (Tables)

Stockholders’ Equity (Tables)	12 Months Ended
	Dec. 31, 2018
Equity [Abstract]
Schedule of Stockholders Equity	On February 6, 2018, the Company filed amended and restated articles of incorporation with the Secretary of State of Florida. Pursuant to the amended and restated articles, the total number of authorized Company shares of all classes is 550,000,000 , consisting of the following classes: Class Number of Par Value Common Stock: Class A 400,000,000 $ 0.10 Class B 100,000,000 0.10 500,000,000 Preferred Stock 50,000,000 0.10 550,000,000

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases		Future minimum annual lease payments under such leases are as follows: Years Approximate (in thousands) 2019 $ 6,281 2020 6,223 2021 5,930 2022 5,386 2023 5,069 Thereafter 43,071 $ 71,960
Summary of Financial Instruments Whose Contract Amount Represents Off-Balance Sheet Credit Risk	Financial instruments whose contract amount represents off-balance sheet credit risk at March 31, 2019 are generally short-term and are as follows: (in thousands) Approximate Commitments to extend credit $ 884,142 Credit card facilities 196,901 Standby letters of credit 24,278 Commercial letters of credit 2,589 $ 1,107,910	Financial instruments whose contract amount represents off-balance sheet credit risk at December 31, 2018 are generally short-term and are as follows: (in thousands) Approximate Commitments to extend credit $ 923,424 Credit card facilities 198,500 Standby letters of credit 19,562 Commercial letters of credit 7,670 $ 1,149,156

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are summarized below: March 31, 2019 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 890,458 $ — $ 890,458 Corporate debt securities — 258,342 — 258,342 U.S. government agency debt securities — 215,336 — 215,336 Municipal bonds — 163,988 — 163,988 Mutual funds — 23,467 — 23,467 — 1,551,591 — 1,551,591 Bank owned life insurance — 207,546 — 207,546 Derivative instruments — 4,991 — 4,991 $ — $ 1,764,128 $ — $ 1,764,128 Liabilities Derivative instruments $ — $ 4,991 $ — $ 4,991 December 31, 2018 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 820,779 $ — $ 820,779 Corporate debt securities — 352,555 — 352,555 U.S. government agency debt securities — 216,985 — 216,985 Municipal bonds — 160,212 — 160,212 Mutual funds — 23,110 — 23,110 Commercial paper — 12,410 — 12,410 — 1,586,051 — 1,586,051 Bank owned life insurance — 206,141 — 206,141 Derivative instruments — 11,491 — 11,491 $ — $ 1,803,683 $ — $ 1,803,683 Liabilities Derivative instruments $ — $ 2,388 $ — $ 2,388	Assets and liabilities measured at fair value on a recurring basis are summarized below: December 31, 2018 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 820,779 $ — $ 820,779 Corporate debt securities — 352,555 — 352,555 U.S. government agency debt securities — 216,985 — 216,985 Municipal bonds — 160,212 — 160,212 Mutual funds — 23,110 — 23,110 Commercial paper — 12,410 — 12,410 — 1,586,051 — 1,586,051 Bank owned life insurance — 206,141 — 206,141 Derivative instruments — 11,491 — 11,491 $ — $ 1,803,683 $ — $ 1,803,683 Liabilities Derivative instruments $ — $ 2,388 $ — $ 2,388 December 31, 2017 (in thousands) Quoted Third-Party Internal Total Assets Securities available for sale U.S. government sponsored enterprise debt securities $ — $ 875,666 $ — $ 875,666 Corporate debt securities — 313,392 — 313,392 U.S. government agency debt securities — 291,385 — 291,385 Municipal bonds — 180,396 — 180,396 Mutual funds — 23,617 — 23,617 U.S. treasury securities — 2,701 — 2,701 — 1,687,157 — 1,687,157 Bank owned life insurance — 200,318 — 200,318 Derivative instruments — 7,032 — 7,032 $ — $ 1,894,507 $ — $ 1,894,507 Liabilities Derivative instruments $ — $ 1,570 $ — $ 1,570
Summary of Major Categories of Assets Measured at Fair Value on a Nonrecurring Basis	The following table presents the major category of assets measured at fair value on a nonrecurring basis at March 31, 2019 : March 31, 2019 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Other Unobservable Inputs (Level 3) Total Impairments Description Loans held for sale $ 9,968 $ — $ — $ —	The following table presents the major category of assets measured at fair value on a nonrecurring basis at December 31, 2017 : December 31, 2017 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Other Unobservable Inputs (Level 3) Total Impairments Description Loans held for sale $ 5,611 $ — $ — $ —

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Estimated Fair Value of Financial Instruments Where Fair Value Differs from Carrying Value	The estimated fair value of financial instruments where fair value differs from carrying value are as follows: March 31, 2019 December 31, 2018 (in thousands) Carrying Estimated Carrying Estimated Financial assets Loans $ 2,792,815 $ 2,670,693 $ 2,850,015 $ 2,739,721 Financial liabilities Time deposits 1,770,303 1,772,212 1,745,025 1,740,752 Advances from the FHLB 1,070,000 1,074,596 1,166,000 1,167,213 Junior subordinated debentures 118,110 114,620 118,110 99,450	The estimated fair value of financial instruments where fair value differs from carrying value are as follows: December 31, 2018 December 31, 2017 (in thousands) Carrying Estimated Carrying Estimated Financial assets Loans $ 2,850,015 $ 2,739,721 $ 2,682,790 $ 2,566,197 Financial liabilities Time deposits 1,745,025 1,740,752 1,466,464 1,461,908 Advances from the Federal Home Loan Bank 1,166,000 1,167,213 1,161,000 1,164,686 Junior subordinated debentures 118,110 99,450 118,110 95,979

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2018
Banking and Thrift [Abstract]
Summary of the Bank's and the Company's Actual Capital Amounts and Ratios	The Bank’s actual capital amounts and ratios are presented in the following table: Actual Minimums Required for Capital Adequacy Purposes Regulatory Minimums to be Well Capitalized (in thousands, except percentages) Amount Ratio Amount Ratio Amount Ratio December 31, 2018 Total capital ratio $ 883,746 13.05 % $ 541,564 8.00 % $ 676,955 10.00 % Tier 1 capital ratio 826,114 12.20 % 406,173 6.00 % 541,564 8.00 % Tier 1 leverage ratio 826,114 9.96 % 331,829 4.00 % 414,786 5.00 % Common equity tier 1 (CET1) 826,114 12.20 % 304,630 4.50 % 440,021 6.50 % December 31, 2017 Total capital ratio $ 885,855 12.69 % $ 556,446 8.00 % $ 695,557 10.00 % Tier 1 capital ratio 812,631 11.68 % 417,334 6.00 % 556,446 8.00 % Tier 1 leverage ratio 812,631 9.69 % 335,600 4.00 % 419,500 5.00 % Common equity tier 1 (CET1) 812,631 11.68 % 313,001 4.50 % 452,112 6.50 % The Company’s actual capital amounts and ratios are presented in the following table: Actual Minimums Required for Capital Adequacy Purposes Regulatory Minimums To be Well Capitalized (in thousands, except percentages) Amount Ratio Amount Ratio Amount Ratio December 31, 2018 Total capital ratio $ 916,663 13.54 % $ 541,638 8.00 % $ 677,047 10.00 % Tier 1 capital ratio 859,031 12.69 % 406,228 6.00 % 541,638 8.00 % Tier 1 leverage ratio 859,031 10.34 % 332,190 4.00 % 415,238 5.00 % Common equity tier 1 (CET1) 749,465 11.07 % 304,671 4.50 % 440,080 6.50 % December 31, 2017 Total capital ratio $ 926,049 13.31 % $ 556,578 8.00 % $ 695,722 10.00 % Tier 1 capital ratio 852,825 12.21 % 417,433 6.00 % 556,578 8.00 % Tier 1 leverage ratio 852,825 10.15 % 335,647 4.00 % 419,559 5.00 % Common equity tier 1 (CET1) 753,545 10.68 % 313,075 4.50 % 452,220 6.50 %

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share	The following table shows the calculation of basic and diluted earnings per share: Three months ended March 31, (in thousands, except per share data) 2019 2018 Numerator: Net income available to common stockholders $ 13,071 $ 9,429 Denominator: Basic weighted average shares outstanding 42,755 42,489 Dilutive effect of share-based compensation awards 159 — Diluted weighted average shares outstanding 42,914 42,489 Basic earnings per common share $ 0.31 $ 0.22 Diluted earnings per common share $ 0.30 $ 0.22	The following table shows the calculation of basic and diluted earnings per share: (in thousands, except per share data) 2018 2017 2016 Numerator: Net income available to common stockholders $ 45,833 $ 43,057 $ 23,579 Denominator: Basic weighted averages shares outstanding 42,487 42,489 42,489 Dilutive effect of shared-based compensation awards — — — Diluted weighted average shares outstanding 42,487 42,489 42,489 Basic earnings per common share $ 1.08 $ 1.01 $ 0.55 Diluted earnings per common share $ 1.08 $ 1.01 $ 0.55

Condensed Unconsolidated Hold_2

Condensed Unconsolidated Holding Companies’ Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Condensed Balance Sheets	Condensed Balance Sheets: December 31, (in thousands) 2018 2017 Assets Cash and due from banks $ 32,922 $ 39,089 Investments in subsidiaries 822,940 821,982 Other assets 9,640 9,775 $ 865,502 $ 870,846 Liabilities and Stockholder’s Equity Junior subordinated debentures held by trust subsidiaries $ 118,110 $ 118,110 Other liabilities 1,048 979 Stockholder’s equity 746,344 751,757 $ 865,502 $ 870,846 Condensed Balance Sheets: December 31, (in thousands) 2018 2017 Assets Cash and due from banks $ 1,891 $ 1,420 Investments in subsidiaries 746,344 752,409 Other assets 1,720 1,798 $ 749,955 $ 755,627 Liabilities and Stockholders' Equity Other liabilities $ 2,537 $ 2,177 Stockholders' equity 747,418 753,450 $ 749,955 $ 755,627
Condensed Statements of Income	Condensed Statements of Income: Years ended December 31 (in thousands) 2018 2017 2016 Income: Interest $ 182 $ 85 $ 33 Equity in earnings of subsidiary 60,609 50,982 31,282 Total income 60,791 51,067 31,315 Expenses: Interest Expense 8,086 7,456 7,129 Provision for loan losses — — 1,838 Other expenses 414 1,310 1,361 Total expense 8,500 8,766 10,328 Net income before income tax benefit 52,291 42,301 20,987 Income tax benefit 1,661 2,726 3,031 Net income $ 53,952 $ 45,027 $ 24,018 Condensed Statements of Income: Years ended December 31 (in thousands) 2018 2017 2016 Income: Interest $ 9 $ 3 $ 2 Equity in earnings of subsidiary 53,939 45,008 23,996 Total income 53,948 45,011 23,998 Expenses: Employee compensation and benefit — 350 350 Other expenses 8,018 2,539 250 Total expense 8,018 2,889 600 Net income before income tax benefit 45,930 42,122 23,398 Income tax (expense) benefit (97 ) 935 181 Net income $ 45,833 $ 43,057 $ 23,579
Condensed Statements of Cash Flows	Condensed Statements of Cash Flows: Years ended December 31, (in thousands) 2018 2017 2016 Cash flows from operating activities Net income $ 45,833 $ 43,057 $ 23,579 Adjustments to reconcile net income to net cash used in operating activities - Equity in earnings of subsidiaries (53,939 ) (45,008 ) (23,996 ) Net change in other assets and liabilities 438 1,337 (2 ) Net cash used in operating activities (7,668 ) (614 ) (419 ) Cash flows from investing activities Cash received upon Voting Trust termination 639 — — Dividends from subsidiary 47,500 700 400 Net cash provided by investment activities 48,139 700 400 Cash flows from financing activities Dividends paid (40,000 ) — — Common stock issued - Class A 17,908 — — Repurchase of common stock - Class B (17,908 ) — — Net cash used in financing activities (40,000 ) — — Net increase (decrease) in cash and cash equivalents 471 86 (19 ) Cash and cash equivalents Beginning of year 1,420 1,334 1,353 End of year $ 1,891 $ 1,420 $ 1,334 Condensed Statements of Cash Flows: Years ended December 31, (in thousands) 2018 2017 2016 Cash flows from operating activities Net income $ 53,952 $ 45,027 $ 24,018 Adjustments to reconcile net income to net cash used in operating activities - Equity in earnings of subsidiaries (60,609 ) (50,982 ) (31,282 ) Net change in other assets and liabilities 490 (4 ) (35 ) Net cash used in operating activities (6,167 ) (5,959 ) (7,299 ) Cash flows from investing activities Dividends received from subsidiary 47,500 6,000 6,000 Dividends paid (47,500 ) (700 ) (400 ) Net cash provided by investing activities — 5,300 5,600 Net decrease in cash and cash equivalents (6,167 ) (659 ) (1,699 ) Cash and cash equivalents Beginning of year 39,089 39,748 41,447 End of year $ 32,922 $ 39,089 $ 39,748

Business, Basis of Presentati_4

Business, Basis of Presentation and Summary of Significant Accounting Policies (Details)	Mar. 07, 2019shares	Jun. 30, 2019segment	Mar. 31, 2019USD ($)subsidiarysegment$ / shares	Dec. 31, 2018USD ($)banking_centersubsidiaryoffice$ / shares	Dec. 31, 2017USD ($)$ / shares	Dec. 19, 2018	Jul. 24, 2018	Apr. 02, 2018	Mar. 15, 2018
Class of Stock [Line Items]
Reportable business segments | segment		1	4
Number of subsidiaries | subsidiary			2	2
Number of banking centers | banking_center				23
Distribution Trust Agreement, percentage of common shareholders equity held by trust								80.10%
Distribution Trust Agreement, percentage of retained shareholders equity held by trust								19.90%
Cash reserve balances				$ 200,000	$ 1,200,000
Securities receivable				3,500,000	6,500,000
Unamortized net deferred loan fees and origination costs				7,100,000	7,400,000
Goodwill impairment charge				0	0
Reclassification of tax law impact on AOCI					0
Available for sale			$ 1,551,591,000	1,586,051,000	1,687,157,000
Gross unrealized losses			$ 20,037,000	$ 36,058,000	$ 21,859,000
Class A common stock
Class of Stock [Line Items]
Common stock, par value (in dollars per share) | $ / shares			$ 0.10	$ 0.10	$ 0.10
Class B common stock
Class of Stock [Line Items]
Treasury stock, acquired (in shares) | shares	2,112,321
Common stock, par value (in dollars per share) | $ / shares			$ 0.10	$ 0.10	$ 0.10
Mutual funds
Class of Stock [Line Items]
Available for sale			$ 23,467,000	$ 23,110,000	$ 23,617,000
Gross unrealized losses			$ 800,000	$ 1,156,000	645,000
Accumulated Other Comprehensive Loss
Class of Stock [Line Items]
Reclassification of tax law impact on AOCI					$ 1,094,000
Mercantil Servicios Financieros, C.A. (MSF) | Maximum
Class of Stock [Line Items]
Percent of shares outstanding owned				5.00%
Mercantil Servicios Financieros, C.A. (MSF) | Maximum | Class B common stock
Class of Stock [Line Items]
Percent of shares outstanding owned						5.00%
Florida
Class of Stock [Line Items]
Number of banking centers | banking_center				15
Texas
Class of Stock [Line Items]
Number of banking centers | banking_center				8
Number of loan production offices | office				1,000
New York
Class of Stock [Line Items]
Number of loan production offices | office				1,000
Amerant Bank, N.A
Class of Stock [Line Items]
Ownership percentage of subsidiary			100.00%	100.00%
Mercantil Florida Bancorp, Inc
Class of Stock [Line Items]
Ownership percentage of subsidiary							100.00%
Mercantil Bank Holding Corporation | Mercantil Servicios Financieros, C.A. (MSF)
Class of Stock [Line Items]
Ownership percentage of subsidiary									100.00%

Business, Basis of Presentati_5

Business, Basis of Presentation and Summary of Significant Accounting Policies - Revisions of Loans By Class (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ 60,322	$ 61,762	$ 72,118	$ 72,000	$ 81,751	$ 77,043
Loans held for investment, gross	5,734,438	5,920,175		6,066,225
Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	22,456	22,778	30,503	31,290	30,713	18,331
Loans held for investment, gross	4,359,720	4,355,942		4,082,893
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	29,100	30,018	33,672	32,687	40,897	44,734
Loans held for investment, gross	1,239,525	1,380,428		1,354,755
Loans to financial institutions and acceptances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	106	445	3,671	4,362	5,304	9,226
Loans held for investment, gross	27,985	68,965		497,626
Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	8,660	8,521	4,272	3,661	$ 4,837	$ 4,752
Loans held for investment, gross	107,208	114,840		130,951
Non-owner occupied | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment, gross	1,852,903	1,809,356		1,713,104
Multi-family residential | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment, gross	878,239	909,439		839,709
Land development and construction loans | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment, gross	291,416	326,644		406,940
Commercial real estate | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment, gross	3,022,558	3,045,439		2,959,753
Single-family residential | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment, gross	535,306	533,481		512,754
Owner-occupied | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment, gross	$ 801,856	$ 777,022		610,386
As Reported
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			72,118	72,000
As Reported | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			29,416	30,246
As Reported | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			34,759	33,731
As Reported | Loans to financial institutions and acceptances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			3,671	4,362
As Reported | Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			4,272	3,661
Effect of change
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			0	0
Effect of change | Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			1,087	1,044
Effect of change | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			(1,087)	(1,044)
Effect of change | Loans to financial institutions and acceptances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			0	0
Effect of change | Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			$ 0	$ 0

Business, Basis of Presentati_6

Business, Basis of Presentation and Summary of Significant Accounting Policies - Revisions of Loan Portfolio Delinquencies By Class (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	$ 5,734,438	$ 5,920,175	$ 6,066,225
Past Due	21,877	20,916
Total Loans in Nonaccrual Status	19,769	16,479	26,722
Total Loans 90 Days or More Past Due and Accruing	749	1,303	226
Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	4,359,720	4,355,942	4,082,893
Past Due	15,468	16,897
Total Loans in Nonaccrual Status	12,371	11,672	17,720
Total Loans 90 Days or More Past Due and Accruing	0	419	226
Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	1,239,525	1,380,428	1,354,755
Past Due	4,635	2,406
Total Loans in Nonaccrual Status	7,361	4,772	8,947
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	27,985	68,965	497,626
Past Due	0	0
Total Loans in Nonaccrual Status	0	0	0
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Consumer loans and overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	107,208	114,840	130,951
Past Due	1,774	1,613
Total Loans in Nonaccrual Status	37	35	55	$ 74
Total Loans 90 Days or More Past Due and Accruing	749	884	0
Non-owner occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	1,852,903	1,809,356	1,713,104
Past Due	0	0
Total Loans in Nonaccrual Status	0	0	489
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Multi-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	878,239	909,439	839,709
Past Due	665	0
Total Loans in Nonaccrual Status	665	0	0
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Land development and construction loans | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	291,416	326,644	406,940
Past Due	0	0
Total Loans in Nonaccrual Status	0	0	0
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Commercial real estate | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	3,022,558	3,045,439	2,959,753
Past Due	665	0
Total Loans in Nonaccrual Status	665	0	489
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Single-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	535,306	533,481	512,754
Past Due	12,134	13,751
Total Loans in Nonaccrual Status	6,514	6,689	5,004	8,893
Total Loans 90 Days or More Past Due and Accruing	0	419	226
Owner-occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment, gross	801,856	777,022	610,386
Past Due	2,669	3,146
Total Loans in Nonaccrual Status	5,192	4,983	12,227
Total Loans 90 Days or More Past Due and Accruing	0	0	0
30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	11,948	11,888
30-59 Days | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	8,210	10,710
30-59 Days | Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,151	704
30-59 Days | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days | Consumer loans and overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	587	474	48	1,076
Total Loans in Nonaccrual Status		8	9	22
30-59 Days | Non-owner occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days | Multi-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days | Land development and construction loans | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days | Commercial real estate | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
30-59 Days | Single-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	7,802	7,910	6,025	4,675
Total Loans in Nonaccrual Status		276	584	0
30-59 Days | Owner-occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	408	2,800
60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	4,299	3,801
60-89 Days | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,466	2,496
60-89 Days | Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	399	1,062
60-89 Days | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days | Consumer loans and overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	434	243	18	443
Total Loans in Nonaccrual Status		0	11	0
60-89 Days | Non-owner occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days | Multi-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	665	0
60-89 Days | Land development and construction loans | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
60-89 Days | Commercial real estate | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	665	0
60-89 Days | Single-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	921	2,336	2,193	1,395
Total Loans in Nonaccrual Status		1,703	557	38
60-89 Days | Owner-occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,880	160
Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	5,630	5,227
Greater than 90 Days | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,792	3,691
Greater than 90 Days | Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,085	640
Greater than 90 Days | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Greater than 90 Days | Consumer loans and overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	753	896	0	370
Total Loans in Nonaccrual Status		11	19	9
Greater than 90 Days | Non-owner occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Greater than 90 Days | Multi-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Greater than 90 Days | Land development and construction loans | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Greater than 90 Days | Commercial real estate | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Greater than 90 Days | Single-family residential | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,411	3,505	225	116
Total Loans in Nonaccrual Status		3,086	$ 1,777	$ 6,565
Greater than 90 Days | Owner-occupied | Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 381	$ 186

Business, Basis of Presentati_7

Business, Basis of Presentation and Summary of Significant Accounting Policies - Revisions of Loans by Credit Quality Indicators (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	$ 5,734,438	$ 5,920,175	$ 6,066,225
Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	4,359,720	4,355,942	4,082,893
Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	1,239,525	1,380,428	1,354,755
Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	27,985	68,965	497,626
Consumer loans and overdrafts
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	107,208	114,840	130,951
Pass
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	5,678,007	5,870,758	6,016,604
Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	4,322,857	4,323,581	4,057,597
Pass | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	1,225,901	1,369,434	1,334,543
Pass | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	27,985	68,965	497,626
Pass | Consumer loans and overdrafts
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	101,264	108,778	126,838
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	30,828	29,305	38,450
Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	15,811	16,781	20,225
Substandard | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	9,073	6,462	14,112
Substandard | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Substandard | Consumer loans and overdrafts
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	5,944	6,062	4,113
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	559	589	0
Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Doubtful | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	559	589	0
Doubtful | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Doubtful | Consumer loans and overdrafts
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Loss
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Loss | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Loss | Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Loss | Consumer loans and overdrafts
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Non-owner occupied | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	1,852,903	1,809,356	1,713,104
Non-owner occupied | Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	1,844,618	1,802,573	1,711,595
Non-owner occupied | Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	222	489
Non-owner occupied | Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Non-owner occupied | Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Multi-family residential | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	878,239	909,439	839,709
Multi-family residential | Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	877,574	909,439	839,709
Multi-family residential | Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	665	0	0
Multi-family residential | Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Multi-family residential | Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Land development and construction loans | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	291,416	326,644	406,940
Land development and construction loans | Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	291,416	326,644	406,940
Land development and construction loans | Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Land development and construction loans | Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Land development and construction loans | Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Commercial real estate | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	3,022,558	3,045,439	2,959,753
Commercial real estate | Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	3,013,608	3,038,656	2,958,244
Commercial real estate | Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	665	222	489
Commercial real estate | Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Commercial real estate | Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Single-family residential | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	535,306	533,481	512,754
Single-family residential | Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	528,792	526,373	506,885
Single-family residential | Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	6,514	7,108	5,869
Single-family residential | Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Single-family residential | Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Owner-occupied | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	801,856	777,022	610,386
Owner-occupied | Pass | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	780,457	758,552	592,468
Owner-occupied | Substandard | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	8,632	9,451	13,867
Owner-occupied | Doubtful | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	0	0	0
Owner-occupied | Loss | Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans held for investment, gross	$ 0	$ 0	$ 0

Business, Basis of Presentati_8

Business, Basis of Presentation and Summary of Significant Accounting Policies - Revisions of Allowance For Loan Loss (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Credit Losses
Balances at beginning of the period	$ 61,762	$ 72,000	$ 72,000	$ 81,751	$ 77,043
(Reversal of) provision for loan losses	0	0	375	(3,490)	22,110
Recoveries	172	919	1,947	3,162	5,208
Balances at end of the period	60,322	72,118	61,762	72,000	81,751
Allowance for loan losses by impairment methodology, Individually evaluated	2,795	2,226	2,373	2,866	6,596
Allowance for loan losses by impairment methodology, Collectively evaluated	57,527	69,892	59,389	69,134	75,155
Investment in loans, net of unearned income, Individually evaluated	16,428	26,635	13,458	22,599	69,329
Investment in loans, net of unearned income, Collectively evaluated	5,718,010	5,923,815	5,906,717	6,043,626	5,695,432
Total Loans, Net of Unearned Income	5,734,438	5,950,450	5,920,175	6,066,225	5,764,761
Domestic
Allowance for Credit Losses
Loans charged-off	(1,188)	(401)	(9,695)	(2,500)	(1,814)
International
Allowance for Credit Losses
Loans charged-off	(424)	(400)	(2,865)	(6,923)	(20,796)
Real estate loans
Allowance for Credit Losses
Balances at beginning of the period	22,778	31,290	31,290	30,713	18,331
(Reversal of) provision for loan losses	(322)	(821)	(2,885)	(221)	8,570
Recoveries	0	34	212	895	3,906
Balances at end of the period	22,456	30,503	22,778	31,290	30,713
Allowance for loan losses by impairment methodology, Individually evaluated	0	0	0	0	0
Allowance for loan losses by impairment methodology, Collectively evaluated	22,456	30,503	22,778	31,290	30,713
Investment in loans, net of unearned income, Individually evaluated	711	11,238	717	1,318	13,792
Investment in loans, net of unearned income, Collectively evaluated	3,016,569	2,803,394	3,037,604	2,912,786	2,364,161
Total Loans, Net of Unearned Income	3,017,280	2,814,632	3,038,321	2,914,104	2,377,953
Real estate loans | Domestic
Allowance for Credit Losses
Loans charged-off	0	0	(5,839)	(97)	(94)
Real estate loans | International
Allowance for Credit Losses
Loans charged-off	0	0	0	0	0
Commercial loans
Allowance for Credit Losses
Balances at beginning of the period	30,018	32,687	32,687	40,897	44,734
(Reversal of) provision for loan losses	(31)	535	1,099	(1,027)	16,153
Recoveries	123	832	1,367	962	1,116
Balances at end of the period	29,100	33,672	30,018	32,687	40,897
Allowance for loan losses by impairment methodology, Individually evaluated	1,593	2,226	1,282	2,866	6,596
Allowance for loan losses by impairment methodology, Collectively evaluated	27,507	31,446	28,736	29,821	34,301
Investment in loans, net of unearned income, Individually evaluated	12,325	15,055	9,652	20,907	51,332
Investment in loans, net of unearned income, Collectively evaluated	2,137,165	2,139,788	2,254,607	2,073,351	2,398,552
Total Loans, Net of Unearned Income	2,149,490	2,154,843	2,264,259	2,094,258	2,449,884
Commercial loans | Domestic
Allowance for Credit Losses
Loans charged-off	(992)	(382)	(3,662)	(1,979)	(1,496)
Commercial loans | International
Allowance for Credit Losses
Loans charged-off	(18)	0	(1,473)	(6,166)	(19,610)
Loans to financial institutions and acceptances
Allowance for Credit Losses
Balances at beginning of the period	445	4,362	4,362	5,304	9,226
(Reversal of) provision for loan losses	(339)	(691)	(3,917)	(942)	(3,922)
Recoveries	0	0	0	0	0
Balances at end of the period	106	3,671	445	4,362	5,304
Allowance for loan losses by impairment methodology, Individually evaluated	0	0	0	0	0
Allowance for loan losses by impairment methodology, Collectively evaluated	106	3,671	445	4,362	5,304
Investment in loans, net of unearned income, Individually evaluated	0	0	0	0	0
Investment in loans, net of unearned income, Collectively evaluated	27,985	416,292	69,003	497,626	416,336
Total Loans, Net of Unearned Income	27,985	416,292	69,003	497,626	416,336
Loans to financial institutions and acceptances | Domestic
Allowance for Credit Losses
Loans charged-off	0	0	0	0	0
Loans to financial institutions and acceptances | International
Allowance for Credit Losses
Loans charged-off	0	0	0	0	0
Consumer loans and overdrafts
Allowance for Credit Losses
Balances at beginning of the period	8,521	3,661	3,661	4,837	4,752
(Reversal of) provision for loan losses	692	977	6,078	(1,300)	1,309
Recoveries	49	53	368	1,305	186
Balances at end of the period	8,660	4,272	8,521	3,661	4,837
Allowance for loan losses by impairment methodology, Individually evaluated	1,202	0	1,091	0	0
Allowance for loan losses by impairment methodology, Collectively evaluated	7,458	4,272	7,430	3,661	4,837
Investment in loans, net of unearned income, Individually evaluated	3,392	342	3,089	374	4,205
Investment in loans, net of unearned income, Collectively evaluated	536,291	564,341	545,503	559,863	516,383
Total Loans, Net of Unearned Income	539,683	564,683	548,592	560,237	520,588
Consumer loans and overdrafts | Domestic
Allowance for Credit Losses
Loans charged-off	(196)	(19)	(194)	(424)	(224)
Consumer loans and overdrafts | International
Allowance for Credit Losses
Loans charged-off	$ (406)	(400)	(1,392)	(757)	$ (1,186)
As Reported
Allowance for Credit Losses
Balances at beginning of the period		72,000	72,000
(Reversal of) provision for loan losses		0
Recoveries		919
Balances at end of the period		72,118		72,000
Allowance for loan losses by impairment methodology, Individually evaluated		2,226
Allowance for loan losses by impairment methodology, Collectively evaluated		69,892
Investment in loans, net of unearned income, Individually evaluated		26,635
Investment in loans, net of unearned income, Collectively evaluated		5,923,815
Total Loans, Net of Unearned Income		5,950,450
As Reported | Domestic
Allowance for Credit Losses
Loans charged-off		(401)
As Reported | International
Allowance for Credit Losses
Loans charged-off		(400)
As Reported | Real estate loans
Allowance for Credit Losses
Balances at beginning of the period		30,246	30,246
(Reversal of) provision for loan losses		(864)
Recoveries		34
Balances at end of the period		29,416		30,246
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		29,416
Investment in loans, net of unearned income, Individually evaluated		11,238
Investment in loans, net of unearned income, Collectively evaluated		2,699,872
Total Loans, Net of Unearned Income		2,711,110
As Reported | Real estate loans | Domestic
Allowance for Credit Losses
Loans charged-off		0
As Reported | Real estate loans | International
Allowance for Credit Losses
Loans charged-off		0
As Reported | Commercial loans
Allowance for Credit Losses
Balances at beginning of the period		33,731	33,731
(Reversal of) provision for loan losses		578
Recoveries		832
Balances at end of the period		34,759		33,731
Allowance for loan losses by impairment methodology, Individually evaluated		2,226
Allowance for loan losses by impairment methodology, Collectively evaluated		32,533
Investment in loans, net of unearned income, Individually evaluated		15,055
Investment in loans, net of unearned income, Collectively evaluated		2,243,345
Total Loans, Net of Unearned Income		2,258,400
As Reported | Commercial loans | Domestic
Allowance for Credit Losses
Loans charged-off		(382)
As Reported | Commercial loans | International
Allowance for Credit Losses
Loans charged-off		0
As Reported | Loans to financial institutions and acceptances
Allowance for Credit Losses
Balances at beginning of the period		4,362	4,362
(Reversal of) provision for loan losses		(691)
Recoveries		0
Balances at end of the period		3,671		4,362
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		3,671
Investment in loans, net of unearned income, Individually evaluated		0
Investment in loans, net of unearned income, Collectively evaluated		416,292
Total Loans, Net of Unearned Income		416,292
As Reported | Loans to financial institutions and acceptances | Domestic
Allowance for Credit Losses
Loans charged-off		0
As Reported | Loans to financial institutions and acceptances | International
Allowance for Credit Losses
Loans charged-off		0
As Reported | Consumer loans and overdrafts
Allowance for Credit Losses
Balances at beginning of the period		3,661	3,661
(Reversal of) provision for loan losses		977
Recoveries		53
Balances at end of the period		4,272		3,661
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		4,272
Investment in loans, net of unearned income, Individually evaluated		342
Investment in loans, net of unearned income, Collectively evaluated		564,306
Total Loans, Net of Unearned Income		564,648
As Reported | Consumer loans and overdrafts | Domestic
Allowance for Credit Losses
Loans charged-off		(19)
As Reported | Consumer loans and overdrafts | International
Allowance for Credit Losses
Loans charged-off		(400)
Effect of change
Allowance for Credit Losses
Balances at beginning of the period		0	0
(Reversal of) provision for loan losses		0
Recoveries		0
Balances at end of the period		0		0
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		0
Investment in loans, net of unearned income, Individually evaluated		0
Investment in loans, net of unearned income, Collectively evaluated		0
Total Loans, Net of Unearned Income		0
Effect of change | Domestic
Allowance for Credit Losses
Loans charged-off		0
Effect of change | International
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Real estate loans
Allowance for Credit Losses
Balances at beginning of the period		1,044	1,044
(Reversal of) provision for loan losses		43
Recoveries		0
Balances at end of the period		1,087		1,044
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		1,087
Investment in loans, net of unearned income, Individually evaluated		0
Investment in loans, net of unearned income, Collectively evaluated		103,522
Total Loans, Net of Unearned Income		103,522
Effect of change | Real estate loans | Domestic
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Real estate loans | International
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Commercial loans
Allowance for Credit Losses
Balances at beginning of the period		(1,044)	(1,044)
(Reversal of) provision for loan losses		(43)
Recoveries		0
Balances at end of the period		(1,087)		(1,044)
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		(1,087)
Investment in loans, net of unearned income, Individually evaluated		0
Investment in loans, net of unearned income, Collectively evaluated		(103,557)
Total Loans, Net of Unearned Income		(103,557)
Effect of change | Commercial loans | Domestic
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Commercial loans | International
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Loans to financial institutions and acceptances
Allowance for Credit Losses
Balances at beginning of the period		0	0
(Reversal of) provision for loan losses		0
Recoveries		0
Balances at end of the period		0		0
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		0
Investment in loans, net of unearned income, Individually evaluated		0
Investment in loans, net of unearned income, Collectively evaluated		0
Total Loans, Net of Unearned Income		0
Effect of change | Loans to financial institutions and acceptances | Domestic
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Loans to financial institutions and acceptances | International
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Consumer loans and overdrafts
Allowance for Credit Losses
Balances at beginning of the period		0	$ 0
(Reversal of) provision for loan losses		0
Recoveries		0
Balances at end of the period		0		$ 0
Allowance for loan losses by impairment methodology, Individually evaluated		0
Allowance for loan losses by impairment methodology, Collectively evaluated		0
Investment in loans, net of unearned income, Individually evaluated		0
Investment in loans, net of unearned income, Collectively evaluated		35
Total Loans, Net of Unearned Income		35
Effect of change | Consumer loans and overdrafts | Domestic
Allowance for Credit Losses
Loans charged-off		0
Effect of change | Consumer loans and overdrafts | International
Allowance for Credit Losses
Loans charged-off		$ 0

Business, Basis of Presentati_9

Business, Basis of Presentation and Summary of Significant Accounting Policies - Revisions of Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	$ 10,945	$ 7,849	$ 7,173
Recorded Investment, Without a Valuation Allowance	5,483	5,609	15,426
Recorded Investment, Total	16,428	13,458	22,599
Year Average	22,471	25,708	44,233
Total Unpaid Principal Balance	17,671	14,776	29,635
Valuation Allowance	2,795	2,373	2,866
Real estate loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	3,774	3,255	0
Recorded Investment, Without a Valuation Allowance	5,352	5,450	13,440
Recorded Investment, Total	9,126	8,705	13,440
Year Average	15,276	18,229	26,022
Total Unpaid Principal Balance	9,233	8,750	14,851
Valuation Allowance	1,505	1,310	0
Real estate loans | Non-owner occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0	0	0
Recorded Investment, Without a Valuation Allowance	0	0	327
Recorded Investment, Total	0	0	327
Year Average	5,188	7,935	225
Total Unpaid Principal Balance	0	0	327
Valuation Allowance	0	0	0
Real estate loans | Multi-family residential
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0	0	0
Recorded Investment, Without a Valuation Allowance	711	717	1,318
Recorded Investment, Total	711	717	1,318
Year Average	719	724	7,898
Total Unpaid Principal Balance	716	722	1,330
Valuation Allowance	0	0	0
Real estate loans | Land development and construction loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0	0	0
Recorded Investment, Without a Valuation Allowance	0	0	0
Recorded Investment, Total	0	0	0
Year Average	0	0	1,359
Total Unpaid Principal Balance	0	0	0
Valuation Allowance	0	0	0
Real estate loans | Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0	0	0
Recorded Investment, Without a Valuation Allowance	711	717	1,645
Recorded Investment, Total	711	717	1,645
Year Average	5,907	8,659	9,482
Total Unpaid Principal Balance	716	722	1,657
Valuation Allowance	0	0	0
Real estate loans | Single-family residential
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	3,411	3,086	0
Recorded Investment, Without a Valuation Allowance	289	306	877
Recorded Investment, Total	3,700	3,392	877
Year Average	4,182	4,046	3,100
Total Unpaid Principal Balance	3,802	3,427	871
Valuation Allowance	1,346	1,235	0
Real estate loans | Owner-occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	363	169	0
Recorded Investment, Without a Valuation Allowance	4,352	4,427	10,918
Recorded Investment, Total	4,715	4,596	10,918
Year Average	5,187	5,524	13,440
Total Unpaid Principal Balance	4,715	4,601	12,323
Valuation Allowance	159	75	0
Commercial loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	7,169	4,585	7,173
Recorded Investment, Without a Valuation Allowance	120	148	1,986
Recorded Investment, Total	7,289	4,733	9,159
Year Average	7,178	7,464	18,211
Total Unpaid Principal Balance	8,427	6,009	14,784
Valuation Allowance	$ 1,289	$ 1,059	$ 2,866

Interest Earning Deposits wit_2

Interest Earning Deposits with Banks (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2019	Dec. 31, 2017
Cash and Cash Equivalents [Abstract]
Interest earning deposits with banks	$ 59,954	$ 62,868	$ 108,914
Average interest rate on deposits with banks	1.88%		1.10%
Interest earning deposits with banks, maturity	1 year

Securities - Amortized Cost to

Securities - Amortized Cost to Fair Value of Available for Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,563,195	$ 1,619,196	$ 1,700,571
Gross Unrealized Gains	8,433	2,913	8,445
Gross Unrealized Losses	(20,037)	(36,058)	(21,859)
Estimated Fair Value	1,551,591	1,586,051	1,687,157
U.S. government sponsored enterprise debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	899,571	840,760	889,396
Gross Unrealized Gains	4,687	2,197	1,784
Gross Unrealized Losses	(13,800)	(22,178)	(15,514)
Estimated Fair Value	890,458	820,779	875,666
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	258,421	357,602	310,781
Gross Unrealized Gains	1,089	139	3,446
Gross Unrealized Losses	(1,168)	(5,186)	(835)
Estimated Fair Value	258,342	352,555	313,392
U.S. government agency debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	218,813	221,682	293,908
Gross Unrealized Gains	362	187	870
Gross Unrealized Losses	(3,839)	(4,884)	(3,393)
Estimated Fair Value	215,336	216,985	291,385
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	162,123	162,438	179,524
Gross Unrealized Gains	2,295	390	2,343
Gross Unrealized Losses	(430)	(2,616)	(1,471)
Estimated Fair Value	163,988	160,212	180,396
Mutual funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	24,267	24,266	24,262
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	(800)	(1,156)	(645)
Estimated Fair Value	23,467	23,110	23,617
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	12,448
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(38)
Estimated Fair Value	$ 0	$ 12,410
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost			2,700
Gross Unrealized Gains			2
Gross Unrealized Losses			(1)
Estimated Fair Value			$ 2,701

Securities - Narrative (Details

Securities - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Available for sale	$ 1,586,051,000	$ 1,687,157,000	$ 1,551,591,000
Proceeds from sales and calls of securities available-for-sale	67,000,000	393,000,000
Gross realized gain	500,000	2,600,000
Gross realized loss	1,400,000	4,200,000
Foreign sovereign debt securities
Debt Securities, Available-for-sale [Line Items]
Available for sale	0	0	$ 0
Collateral Pledged
Debt Securities, Available-for-sale [Line Items]
Securities available for sale with a fair value, pledged as collateral	$ 50,000,000	$ 246,000,000

Securities - Unrealized Loss on

Securities - Unrealized Loss on Available for Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	$ 189,717	$ 412,086	$ 524,751
12 Months or More, Estimated Fair Value	808,585	935,330	719,142
Total, Estimated Fair Value	998,302	1,347,416	1,243,893
Less Than 12 Months, Unrealized Loss	(2,796)	(7,778)	(4,443)
12 Months or More, Unrealized Loss	(17,241)	(28,280)	(17,416)
Total, Unrealized Loss	(20,037)	(36,058)	(21,859)
U.S. government sponsored enterprise debt securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	74,413	90,980	333,232
12 Months or More, Estimated Fair Value	524,470	608,486	485,555
Total, Estimated Fair Value	598,883	699,466	818,787
Less Than 12 Months, Unrealized Loss	(1,995)	(2,995)	(2,956)
12 Months or More, Unrealized Loss	(11,805)	(19,183)	(12,558)
Total, Unrealized Loss	(13,800)	(22,178)	(15,514)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	72,106	243,667	94,486
12 Months or More, Estimated Fair Value	75,776	75,762	3,694
Total, Estimated Fair Value	147,882	319,429	98,180
Less Than 12 Months, Unrealized Loss	(365)	(3,800)	(751)
12 Months or More, Unrealized Loss	(803)	(1,386)	(84)
Total, Unrealized Loss	(1,168)	(5,186)	(835)
U.S. government agency debt securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	43,198	1,449	92,138
12 Months or More, Estimated Fair Value	136,260	94,331	128,316
Total, Estimated Fair Value	179,458	95,780	220,454
Less Than 12 Months, Unrealized Loss	(436)	(6)	(728)
12 Months or More, Unrealized Loss	(3,403)	(2,610)	(2,665)
Total, Unrealized Loss	(3,839)	(2,616)	(3,393)
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	0	63,580	4,895
12 Months or More, Estimated Fair Value	48,859	133,886	76,003
Total, Estimated Fair Value	48,859	197,466	80,898
Less Than 12 Months, Unrealized Loss	0	(939)	(8)
12 Months or More, Unrealized Loss	(430)	(3,945)	(1,463)
Total, Unrealized Loss	(430)	(4,884)	(1,471)
Mutual funds
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	0	0	0
12 Months or More, Estimated Fair Value	23,220	22,865	23,375
Total, Estimated Fair Value	23,220	22,865	23,375
Less Than 12 Months, Unrealized Loss	0	0	0
12 Months or More, Unrealized Loss	(800)	(1,156)	(645)
Total, Unrealized Loss	(800)	(1,156)	(645)
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value		1,449	0
12 Months or More, Estimated Fair Value		94,331	2,199
Total, Estimated Fair Value		95,780	2,199
Less Than 12 Months, Unrealized Loss		(6)	0
12 Months or More, Unrealized Loss		(2,610)	(1)
Total, Unrealized Loss		(2,616)	$ (1)
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Estimated Fair Value	0	12,410
12 Months or More, Estimated Fair Value	0	0
Total, Estimated Fair Value	0	12,410
Less Than 12 Months, Unrealized Loss	0	(38)
12 Months or More, Unrealized Loss	0	0
Total, Unrealized Loss	$ 0	$ (38)

Securities - Held to Maturity S

Securities - Held to Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 83,909	$ 85,188	$ 89,860
Gross Unrealized Gains	101	0	47
Gross Unrealized Losses	(1,635)	(3,938)	(441)
Estimated Fair Value	82,375	81,250	89,466
U.S. government sponsored enterprise debt securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	81,088	82,326	86,826
Gross Unrealized Gains	79	0	47
Gross Unrealized Losses	(1,635)	(3,889)	(441)
Estimated Fair Value	79,532	78,437	86,432
Corporate debt securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	2,821	2,862	3,034
Gross Unrealized Gains	22	0	0
Gross Unrealized Losses	0	(49)	0
Estimated Fair Value	$ 2,843	$ 2,813	$ 3,034

Securities - Contractual Maturi

Securities - Contractual Maturities on Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Available for Sale, Amortized Cost
Within 1 year	$ 34,856	$ 54,477
After 1 year through 5 years	239,679	330,024
After 5 years through 10 years	172,190	166,152
After 10 years	1,092,203	1,044,277
No contractual maturities	24,267	24,266
Amortized Cost	1,563,195	1,619,196	$ 1,700,571
Available for Sale, Estimated Fair Value
Within 1 year	34,769	54,306
After 1 year through 5 years	239,297	325,752
After 5 years through 10 years	172,421	163,039
After 10 years	1,081,637	1,019,844
No contractual maturities	23,467	23,110
Estimated Fair Value	1,551,591	1,586,051	1,687,157
Held to Maturity, Amortized Cost
Within 1 year	0	0
After 1 year through 5 years	0	0
After 5 years through 10 years	0	0
After 10 years	83,909	85,188
No contractual maturities	0	0
Amortized Cost	83,909	85,188	89,860
Held to Maturity, Estimated Fair Value
Within 1 year	0	0
After 1 year through 5 years	0	0
After 5 years through 10 years	0	0
After 10 years	82,375	81,250
No contractual maturities	0	0
Estimated Fair Value	$ 82,375	$ 81,250	$ 89,466

Loans - Loan Portfolio by Class

Loans - Loan Portfolio by Classes (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,734,438	$ 5,920,175	$ 6,066,225
Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,359,720	4,355,942	4,082,893
Real estate loans | Nonowner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,852,903	1,809,356	1,713,104
Real estate loans | Multi-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	878,239	909,439	839,709
Real estate loans | Land development and construction loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	291,416	326,644	406,940
Real estate loans | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,022,558	3,045,439	2,959,753
Real estate loans | Single-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	535,306	533,481	512,754
Real estate loans | Owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	801,856	777,022	610,386
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,239,525	1,380,428	1,354,755
Loans to financial institutions and acceptances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	27,985	68,965	497,626
Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 107,208	$ 114,840	$ 130,951

Loans - Narrative (Details)

Loans - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Receivables [Abstract]
Syndication facilities included in loans	$ 640	$ 807	$ 989
Cash collateral on loans	18.4	19.5	31.9
Loans pledged as collateral	$ 1,289	$ 1,680	$ 1,476

Loans - Loan Portfolio by Count

Loans - Loan Portfolio by Countries (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 5,734,438	$ 5,920,175	$ 6,066,225
Others | Assets, total | Geographic concentration risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk, percentage	1.00%	1.00%	1.00%
International
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 236,349	$ 299,759	$ 755,269
International | Brazil
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			141,088
International | Venezuela
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	150,535	157,162	182,678
International | Chile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			94,543
International | Others
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	85,814	142,597	336,960
Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,359,720	4,355,942	4,082,893
Real estate loans | International
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	131,297	135,438	152,713
Real estate loans | International | Brazil
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			219
Real estate loans | International | Venezuela
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	124,772	128,971	145,069
Real estate loans | International | Chile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			179
Real estate loans | International | Others
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	6,525	6,467	7,246
Loans to financial institutions and acceptances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	27,985	68,965	497,626
Loans to financial institutions and acceptances | International
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	8,000	49,000	481,183
Loans to financial institutions and acceptances | International | Brazil
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			129,372
Loans to financial institutions and acceptances | International | Venezuela
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
Loans to financial institutions and acceptances | International | Chile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			93,000
Loans to financial institutions and acceptances | International | Others
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	8,000	49,000	258,811
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,239,525	1,380,428	1,354,755
Commercial loans | International
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	63,061	73,636	69,294
Commercial loans | International | Brazil
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			8,451
Commercial loans | International | Venezuela
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
Commercial loans | International | Chile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			0
Commercial loans | International | Others
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	63,061	73,636	60,843
Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	107,208	114,840	130,951
Consumer loans and overdrafts | International
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	33,991	41,685	52,079
Consumer loans and overdrafts | International | Brazil
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			3,046
Consumer loans and overdrafts | International | Venezuela
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	25,763	28,191	37,609
Consumer loans and overdrafts | International | Chile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans			1,364
Consumer loans and overdrafts | International | Others
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 8,228	$ 13,494	$ 10,060

Loans - Loans by Delinquency (D

Loans - Loans by Delinquency (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	$ 5,734,438	$ 5,920,175	$ 6,066,225
Current	5,712,561	5,899,259	6,042,448
Past Due		20,916	23,777
Total Loans in Nonaccrual Status	19,769	16,479	26,722
Total Loans 90 Days or More Past Due and Accruing	749	1,303	226
30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		11,888	10,051
60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		3,801	2,958
Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		5,227	10,768
Real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	4,359,720	4,355,942	4,082,893
Current	4,344,252	4,339,045	4,063,309
Past Due		16,897	19,584
Total Loans in Nonaccrual Status	12,371	11,672	17,720
Total Loans 90 Days or More Past Due and Accruing	0	419	226
Real estate loans | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		10,710	9,609
Real estate loans | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,496	2,924
Real estate loans | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		3,691	7,051
Real estate loans | Non-owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	1,852,903	1,809,356	1,713,104
Current	1,852,903	1,809,356	1,712,624
Past Due		0	480
Total Loans in Nonaccrual Status	0	0	489
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Real estate loans | Non-owner occupied | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Non-owner occupied | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Non-owner occupied | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	480
Real estate loans | Multi-family residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	878,239	909,439	839,709
Current	877,574	909,439	839,709
Past Due		0	0
Total Loans in Nonaccrual Status	665	0	0
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Real estate loans | Multi-family residential | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Multi-family residential | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Multi-family residential | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Land development and construction loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	291,416	326,644	406,940
Current	291,416	326,644	406,940
Past Due		0	0
Total Loans in Nonaccrual Status	0	0	0
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Real estate loans | Land development and construction loans | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Land development and construction loans | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Land development and construction loans | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	3,022,558	3,045,439	2,959,753
Current	3,021,893	3,045,439	2,959,273
Past Due		0	480
Total Loans in Nonaccrual Status	665	0	489
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Real estate loans | Commercial real estate | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Commercial real estate | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Real estate loans | Commercial real estate | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	480
Real estate loans | Single-family residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	535,306	533,481	512,754
Current	523,172	519,730	501,393
Past Due		13,751	11,361
Total Loans in Nonaccrual Status	6,514	6,689	5,004	$ 8,893
Total Loans 90 Days or More Past Due and Accruing	0	419	226
Real estate loans | Single-family residential | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		7,910	6,609
Total Loans in Nonaccrual Status		276	584	0
Real estate loans | Single-family residential | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,336	2,750
Total Loans in Nonaccrual Status		1,703	557	38
Real estate loans | Single-family residential | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		3,505	2,002
Total Loans in Nonaccrual Status		3,086	1,777	6,565
Real estate loans | Owner-occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	801,856	777,022	610,386
Current	799,187	773,876	602,643
Past Due		3,146	7,743
Total Loans in Nonaccrual Status	5,192	4,983	12,227
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Real estate loans | Owner-occupied | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,800	3,000
Real estate loans | Owner-occupied | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		160	174
Real estate loans | Owner-occupied | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		186	4,569
Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	1,239,525	1,380,428	1,354,755
Current	1,234,890	1,378,022	1,350,667
Past Due		2,406	4,088
Total Loans in Nonaccrual Status	7,361	4,772	8,947
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Commercial loans | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		704	385
Commercial loans | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,062	5
Commercial loans | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		640	3,698
Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	27,985	68,965	497,626
Current	27,985	68,965	497,626
Past Due		0	0
Total Loans in Nonaccrual Status	0	0	0
Total Loans 90 Days or More Past Due and Accruing	0	0	0
Loans to financial institutions and acceptances | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Loans to financial institutions and acceptances | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Loans to financial institutions and acceptances | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0
Consumer loans and overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans, Net of Unearned Income	107,208	114,840	130,951
Current	105,434	113,227	130,846
Past Due		1,613	105
Total Loans in Nonaccrual Status	37	35	55	74
Total Loans 90 Days or More Past Due and Accruing	$ 749	884	0
Consumer loans and overdrafts | 30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		474	57
Total Loans in Nonaccrual Status		8	9	22
Consumer loans and overdrafts | 60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		243	29
Total Loans in Nonaccrual Status		0	11	0
Consumer loans and overdrafts | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		896	19
Total Loans in Nonaccrual Status		$ 11	$ 19	$ 9

Allowance for Loan Losses - All

Allowance for Loan Losses - Allowances by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balances at beginning of the period	$ 61,762	$ 72,000	$ 72,000	$ 81,751	$ 77,043
(Reversal of) provision for loan losses	0	0	375	(3,490)	22,110
Recoveries	172	919	1,947	3,162	5,208
Balances at end of the period	60,322	72,118	61,762	72,000	81,751
Allowance for loan losses by impairment methodology, Individually evaluated	2,795	2,226	2,373	2,866	6,596
Allowance for loan losses by impairment methodology, Collectively evaluated	57,527	69,892	59,389	69,134	75,155
Investment in loans, net of unearned income, Individually evaluated	16,428	26,635	13,458	22,599	69,329
Investment in loans, net of unearned income, Collectively evaluated	5,718,010	5,923,815	5,906,717	6,043,626	5,695,432
Total Loans, Net of Unearned Income	5,734,438	5,950,450	5,920,175	6,066,225	5,764,761
Domestic
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	(1,188)	(401)	(9,695)	(2,500)	(1,814)
International
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	(424)	(400)	(2,865)	(6,923)	(20,796)
Real estate loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balances at beginning of the period	22,778	31,290	31,290	30,713	18,331
(Reversal of) provision for loan losses	(322)	(821)	(2,885)	(221)	8,570
Recoveries	0	34	212	895	3,906
Balances at end of the period	22,456	30,503	22,778	31,290	30,713
Allowance for loan losses by impairment methodology, Individually evaluated	0	0	0	0	0
Allowance for loan losses by impairment methodology, Collectively evaluated	22,456	30,503	22,778	31,290	30,713
Investment in loans, net of unearned income, Individually evaluated	711	11,238	717	1,318	13,792
Investment in loans, net of unearned income, Collectively evaluated	3,016,569	2,803,394	3,037,604	2,912,786	2,364,161
Total Loans, Net of Unearned Income	3,017,280	2,814,632	3,038,321	2,914,104	2,377,953
Real estate loans | Domestic
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	0	0	(5,839)	(97)	(94)
Real estate loans | International
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	0	0	0	0	0
Commercial loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balances at beginning of the period	30,018	32,687	32,687	40,897	44,734
(Reversal of) provision for loan losses	(31)	535	1,099	(1,027)	16,153
Recoveries	123	832	1,367	962	1,116
Balances at end of the period	29,100	33,672	30,018	32,687	40,897
Allowance for loan losses by impairment methodology, Individually evaluated	1,593	2,226	1,282	2,866	6,596
Allowance for loan losses by impairment methodology, Collectively evaluated	27,507	31,446	28,736	29,821	34,301
Investment in loans, net of unearned income, Individually evaluated	12,325	15,055	9,652	20,907	51,332
Investment in loans, net of unearned income, Collectively evaluated	2,137,165	2,139,788	2,254,607	2,073,351	2,398,552
Total Loans, Net of Unearned Income	2,149,490	2,154,843	2,264,259	2,094,258	2,449,884
Commercial loans | Domestic
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	(992)	(382)	(3,662)	(1,979)	(1,496)
Commercial loans | International
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	(18)	0	(1,473)	(6,166)	(19,610)
Loans to financial institutions and acceptances
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balances at beginning of the period	445	4,362	4,362	5,304	9,226
(Reversal of) provision for loan losses	(339)	(691)	(3,917)	(942)	(3,922)
Recoveries	0	0	0	0	0
Balances at end of the period	106	3,671	445	4,362	5,304
Allowance for loan losses by impairment methodology, Individually evaluated	0	0	0	0	0
Allowance for loan losses by impairment methodology, Collectively evaluated	106	3,671	445	4,362	5,304
Investment in loans, net of unearned income, Individually evaluated	0	0	0	0	0
Investment in loans, net of unearned income, Collectively evaluated	27,985	416,292	69,003	497,626	416,336
Total Loans, Net of Unearned Income	27,985	416,292	69,003	497,626	416,336
Loans to financial institutions and acceptances | Domestic
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	0	0	0	0	0
Loans to financial institutions and acceptances | International
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	0	0	0	0	0
Consumer loans and overdrafts
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balances at beginning of the period	8,521	3,661	3,661	4,837	4,752
(Reversal of) provision for loan losses	692	977	6,078	(1,300)	1,309
Recoveries	49	53	368	1,305	186
Balances at end of the period	8,660	4,272	8,521	3,661	4,837
Allowance for loan losses by impairment methodology, Individually evaluated	1,202	0	1,091	0	0
Allowance for loan losses by impairment methodology, Collectively evaluated	7,458	4,272	7,430	3,661	4,837
Investment in loans, net of unearned income, Individually evaluated	3,392	342	3,089	374	4,205
Investment in loans, net of unearned income, Collectively evaluated	536,291	564,341	545,503	559,863	516,383
Total Loans, Net of Unearned Income	539,683	564,683	548,592	560,237	520,588
Consumer loans and overdrafts | Domestic
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	(196)	(19)	(194)	(424)	(224)
Consumer loans and overdrafts | International
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Loans charged-off	$ (406)	$ (400)	$ (1,392)	$ (757)	$ (1,186)

Allowance for Loan Losses - Rec

Allowance for Loan Losses - Recorded Investment of Loan Sales (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Amount of loan sales	$ 152,177	$ 12,958	$ 173,473	$ 90,477	$ 105,248
Real estate loans
Financing Receivable, Impaired [Line Items]
Amount of loan sales	23,475	2,958	20,248	15,040	9,151
Commercial loans
Financing Receivable, Impaired [Line Items]
Amount of loan sales	126,838	10,000	138,244	35,260	72,597
Loans to financial institutions and acceptances
Financing Receivable, Impaired [Line Items]
Amount of loan sales	0	0	0	40,177	23,500
Consumer loans and overdrafts
Financing Receivable, Impaired [Line Items]
Amount of loan sales	$ 1,864	$ 0	$ 14,981	$ 0	$ 0

Allowance for Loan Losses - Imp

Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	$ 10,945		$ 7,849	$ 7,173
Recorded Investment, Without a Valuation Allowance	5,483		5,609	15,426
Recorded Investment, Total	16,428		13,458	22,599
Year Average	22,471		25,708	44,233
Total Unpaid Principal Balance	17,671		14,776	29,635
Valuation Allowance	2,795		2,373	2,866
Interest Income Recognized	18	$ 25	1,106	1,178
Real estate loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	3,774		3,255	0
Recorded Investment, Without a Valuation Allowance	5,352		5,450	13,440
Recorded Investment, Total	9,126		8,705	13,440
Year Average	15,276		18,229	26,022
Total Unpaid Principal Balance	9,233		8,750	14,851
Valuation Allowance	1,505		1,310	0
Interest Income Recognized			154	1,166
Real estate loans | Non-owner occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0		0	0
Recorded Investment, Without a Valuation Allowance	0		0	327
Recorded Investment, Total	0		0	327
Year Average	5,188		7,935	225
Total Unpaid Principal Balance	0		0	327
Valuation Allowance	0		0	0
Interest Income Recognized			0	0
Real estate loans | Multi-family residential
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0		0	0
Recorded Investment, Without a Valuation Allowance	711		717	1,318
Recorded Investment, Total	711		717	1,318
Year Average	719		724	7,898
Total Unpaid Principal Balance	716		722	1,330
Valuation Allowance	0		0	0
Interest Income Recognized			32	54
Real estate loans | Land development and construction loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0		0	0
Recorded Investment, Without a Valuation Allowance	0		0	0
Recorded Investment, Total	0		0	0
Year Average	0		0	1,359
Total Unpaid Principal Balance	0		0	0
Valuation Allowance	0		0	0
Interest Income Recognized			0	0
Real estate loans | Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	0		0	0
Recorded Investment, Without a Valuation Allowance	711		717	1,645
Recorded Investment, Total	711		717	1,645
Year Average	5,907		8,659	9,482
Total Unpaid Principal Balance	716		722	1,657
Valuation Allowance	0		0	0
Interest Income Recognized			32	54
Real estate loans | Single-family residential
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	3,411		3,086	0
Recorded Investment, Without a Valuation Allowance	289		306	877
Recorded Investment, Total	3,700		3,392	877
Year Average	4,182		4,046	3,100
Total Unpaid Principal Balance	3,802		3,427	871
Valuation Allowance	1,346		1,235	0
Interest Income Recognized			108	1,101
Real estate loans | Owner-occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	363		169	0
Recorded Investment, Without a Valuation Allowance	4,352		4,427	10,918
Recorded Investment, Total	4,715		4,596	10,918
Year Average	5,187		5,524	13,440
Total Unpaid Principal Balance	4,715		4,601	12,323
Valuation Allowance	159		75	0
Interest Income Recognized			14	11
Commercial loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	7,169		4,585	7,173
Recorded Investment, Without a Valuation Allowance	120		148	1,986
Recorded Investment, Total	7,289		4,733	9,159
Year Average	7,178		7,464	18,211
Total Unpaid Principal Balance	8,427		6,009	14,784
Valuation Allowance	1,289		1,059	2,866
Interest Income Recognized			952	12
Consumer loans and overdrafts
Financing Receivable, Impaired [Line Items]
Recorded Investment, With a Valuation Allowance	2		9	0
Recorded Investment, Without a Valuation Allowance	11		11	0
Recorded Investment, Total	13		20	0
Year Average	17		15	0
Total Unpaid Principal Balance	11		17	0
Valuation Allowance	$ 1		4	0
Interest Income Recognized			$ 0	$ 0

Allowance for Loan Losses - TDR

Allowance for Loan Losses - TDR Loans (Details) contract in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2018USD ($)contract	Dec. 31, 2017USD ($)contract	Dec. 31, 2016USD ($)contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		5	4	7
Recorded Investment		$ 2,463	$ 1,473	$ 12,275
Write-down		$ 6,900	$ 6,000
Real estate loans
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		2	3	5
Recorded Investment		$ 1,831	$ 0	$ 1,103
Real estate loans | Non-owner occupied
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		1	0	1
Recorded Investment		$ 0	$ 0	$ 208
Write-down	$ 10,200
Proceeds from sale	$ 5,800
Real estate loans | Single-family residential
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		0	2	1
Recorded Investment		$ 0	$ 0	$ 49
Real estate loans | Owner-occupied
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		1	1	3
Recorded Investment		$ 1,831	$ 0	$ 846
Commercial loans
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		2	1	2
Recorded Investment		$ 622	$ 1,473	$ 11,172
Consumer loans and overdrafts
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		1	0	0
Recorded Investment		$ 10	$ 0	$ 0

Allowance for Loan Losses - T_2

Allowance for Loan Losses - TDR Loans Subsequently Defaulted (Details) contract in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)contract	Dec. 31, 2017USD ($)contract	Dec. 31, 2016USD ($)contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	3	1	10
Recorded Investment | $	$ 2,430	$ 618	$ 5,969
Real estate loans
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	1	10
Recorded Investment | $	$ 1,831	$ 618	$ 5,969
Real estate loans | Single-family residential
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0	6
Recorded Investment | $	$ 0	$ 0	$ 3,010
Real estate loans | Owner-occupied
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	1	4
Recorded Investment | $	$ 1,831	$ 618	$ 2,959
Commercial loans
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	0	0
Recorded Investment | $	$ 589	$ 0	$ 0
Consumer loans and overdrafts
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	0	0
Recorded Investment | $	$ 10	$ 0	$ 0

Allowance for Loan Losses - Mas

Allowance for Loan Losses - Master Risk Category (Details)	Dec. 31, 2018rating
Pass | Minimum
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	4
Pass | Maximum
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	10
Classified | Minimum
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	1
Classified | Maximum
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	3
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	3
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	2
Loss
Financing Receivable, Recorded Investment [Line Items]
Loan Risk Rating	1

Allowance for Loan Losses - Cre

Allowance for Loan Losses - Credit Risk Quality Indicators (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 5,734,438	$ 5,920,175	$ 6,066,225
Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	5,678,007	5,870,758	6,016,604
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	25,044	19,523	11,171
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	30,828	29,305	38,450
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	559	589	0
Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans	4,359,720	4,355,942	4,082,893
Real estate loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	4,322,857	4,323,581	4,057,597
Real estate loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	21,052	15,580	5,071
Real estate loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	15,811	16,781	20,225
Real estate loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Non-owner occupied
Financing Receivable, Recorded Investment [Line Items]
Loans	1,852,903	1,809,356	1,713,104
Real estate loans | Non-owner occupied | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	1,844,618	1,802,573	1,711,595
Real estate loans | Non-owner occupied | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	8,285	6,561	1,020
Real estate loans | Non-owner occupied | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	0	222	489
Real estate loans | Non-owner occupied | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Non-owner occupied | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Multi-family residential
Financing Receivable, Recorded Investment [Line Items]
Loans	878,239	909,439	839,709
Real estate loans | Multi-family residential | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	877,574	909,439	839,709
Real estate loans | Multi-family residential | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans		0	0
Real estate loans | Multi-family residential | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	665	0	0
Real estate loans | Multi-family residential | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Multi-family residential | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Land development and construction loans
Financing Receivable, Recorded Investment [Line Items]
Loans	291,416	326,644	406,940
Real estate loans | Land development and construction loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	291,416	326,644	406,940
Real estate loans | Land development and construction loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Land development and construction loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Land development and construction loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Land development and construction loans | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans	3,022,558	3,045,439	2,959,753
Real estate loans | Commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	3,013,608	3,038,656	2,958,244
Real estate loans | Commercial real estate | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	8,285	6,561	1,020
Real estate loans | Commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	665	222	489
Real estate loans | Commercial real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Commercial real estate | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Single-family residential
Financing Receivable, Recorded Investment [Line Items]
Loans	535,306	533,481	512,754
Real estate loans | Single-family residential | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	528,792	526,373	506,885
Real estate loans | Single-family residential | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Single-family residential | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	6,514	7,108	5,869
Real estate loans | Single-family residential | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Single-family residential | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Loans	801,856	777,022	610,386
Real estate loans | Owner-occupied | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	780,457	758,552	592,468
Real estate loans | Owner-occupied | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	12,767	9,019	4,051
Real estate loans | Owner-occupied | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	8,632	9,451	13,867
Real estate loans | Owner-occupied | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Real estate loans | Owner-occupied | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans	1,239,525	1,380,428	1,354,755
Commercial loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	1,225,901	1,369,434	1,334,543
Commercial loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	3,992	3,943	6,100
Commercial loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	9,073	6,462	14,112
Commercial loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	559	589	0
Commercial loans | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Loans to financial institutions and acceptances
Financing Receivable, Recorded Investment [Line Items]
Loans	27,985	68,965	497,626
Loans to financial institutions and acceptances | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	27,985	68,965	497,626
Loans to financial institutions and acceptances | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Loans to financial institutions and acceptances | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Loans to financial institutions and acceptances | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Loans to financial institutions and acceptances | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Consumer loans and overdrafts
Financing Receivable, Recorded Investment [Line Items]
Loans	107,208	114,840	130,951
Consumer loans and overdrafts | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans	101,264	108,778	126,838
Consumer loans and overdrafts | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Consumer loans and overdrafts | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	5,944	6,062	4,113
Consumer loans and overdrafts | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0	0
Consumer loans and overdrafts | Loss
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 0	$ 0	$ 0

Allowance for Loan Losses - Acc

Allowance for Loan Losses - Accrual and Non-Accrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accrual Loans, Loan Balance
Past Due	$ 21,877	$ 20,916
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans	19,769	16,479	$ 26,722
30-59 Days Past Due
Accrual Loans, Loan Balance
Past Due	11,948	11,888
60-89 Days Past Due
Accrual Loans, Loan Balance
Past Due	4,299	3,801
90 Days Past Due
Accrual Loans, Loan Balance
Past Due	5,630	5,227
Real estate loans
Accrual Loans, Loan Balance
Past Due	15,468	16,897
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans	12,371	11,672	17,720
Real estate loans | 30-59 Days Past Due
Accrual Loans, Loan Balance
Past Due	8,210	10,710
Real estate loans | 60-89 Days Past Due
Accrual Loans, Loan Balance
Past Due	3,466	2,496
Real estate loans | 90 Days Past Due
Accrual Loans, Loan Balance
Past Due	3,792	3,691
Real estate loans | Single-family residential
Accrual Loans, Loan Balance
Current		518,106	499,307	$ 455,410
Past Due	12,134	13,751
Past due, and still accruing		8,686	8,443	6,186
Total Accrual Loans		$ 526,792	$ 507,750	$ 461,596
Accrued Loans, %
Current loans, still accruing as a percentage of total loans		97.12%	97.38%	96.80%
Total past due loans, still accruing as a percentage of total loans		1.63%	1.64%	1.31%
Current and past due loans still accruing, as a percentage of total loans		98.75%	99.02%	98.11%
Non-Accrual Loans, Loan Balance
Current		$ 1,624	$ 2,086	$ 2,290
Loan Balance		5,065	2,918	6,603
Total Non-Accrual Loans	6,514	$ 6,689	$ 5,004	$ 8,893
Non-Accrual Loans, %
Current nonaccrual loans as a percentage of total loans		0.30%	0.41%	0.49%
Past due non-accrual loans as a percentage of total loans		0.95%	0.57%	1.40%
Total non-accrual loans as a percentage of total loans		1.25%	0.98%	1.89%
Loan Balance		$ 533,481	$ 512,754	$ 470,489
%		100.00%	100.00%	100.00%
Real estate loans | Single-family residential | 30-59 Days Past Due
Accrual Loans, Loan Balance
Past Due		$ 7,634
Past Due	7,802	$ 7,910	$ 6,025	$ 4,675
Accrued Loans, %
Past due loans, still accruing as a percentage of total loans		1.43%	1.17%	0.99%
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans		$ 276	$ 584	$ 0
Non-Accrual Loans, %
Total non-accrual loans as a percentage of total loans		0.05%	0.11%	0.00%
Real estate loans | Single-family residential | 60-89 Days Past Due
Accrual Loans, Loan Balance
Past Due		$ 633
Past Due	921	$ 2,336	$ 2,193	$ 1,395
Accrued Loans, %
Past due loans, still accruing as a percentage of total loans		0.12%	0.43%	0.30%
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans		$ 1,703	$ 557	$ 38
Non-Accrual Loans, %
Total non-accrual loans as a percentage of total loans		0.32%	0.11%	0.01%
Real estate loans | Single-family residential | 90 Days Past Due
Accrual Loans, Loan Balance
Past Due		$ 419
Past Due	3,411	$ 3,505	$ 225	$ 116
Accrued Loans, %
Past due loans, still accruing as a percentage of total loans		0.08%	0.04%	0.02%
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans		$ 3,086	$ 1,777	$ 6,565
Non-Accrual Loans, %
Total non-accrual loans as a percentage of total loans		0.58%	0.35%	1.39%
Consumer loans and overdrafts
Accrual Loans, Loan Balance
Current		$ 113,211	$ 130,830	$ 120,463
Past Due	1,774	1,613
Past due, and still accruing		1,594	66	1,889
Total Accrual Loans		$ 114,805	$ 130,896	$ 122,352
Accrued Loans, %
Current loans, still accruing as a percentage of total loans		98.58%	99.91%	98.40%
Total past due loans, still accruing as a percentage of total loans		1.39%	0.05%	1.54%
Current and past due loans still accruing, as a percentage of total loans		99.97%	99.96%	99.94%
Non-Accrual Loans, Loan Balance
Current		$ 16	$ 16	$ 43
Loan Balance		19	39	31
Total Non-Accrual Loans	37	$ 35	$ 55	$ 74
Non-Accrual Loans, %
Current nonaccrual loans as a percentage of total loans		0.01%	0.01%	0.03%
Past due non-accrual loans as a percentage of total loans		0.02%	0.03%	0.03%
Total non-accrual loans as a percentage of total loans		0.03%	0.04%	0.06%
Loan Balance		$ 114,840	$ 130,951	$ 122,426
%		100.00%	100.00%	100.00%
Consumer loans and overdrafts | 30-59 Days Past Due
Accrual Loans, Loan Balance
Past Due		$ 466
Past Due	587	$ 474	$ 48	$ 1,076
Accrued Loans, %
Past due loans, still accruing as a percentage of total loans		0.41%	0.04%	0.88%
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans		$ 8	$ 9	$ 22
Non-Accrual Loans, %
Total non-accrual loans as a percentage of total loans		0.01%	0.01%	0.02%
Consumer loans and overdrafts | 60-89 Days Past Due
Accrual Loans, Loan Balance
Past Due		$ 243
Past Due	434	$ 243	$ 18	$ 443
Accrued Loans, %
Past due loans, still accruing as a percentage of total loans		0.21%	0.01%	0.36%
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans		$ 0	$ 11	$ 0
Non-Accrual Loans, %
Total non-accrual loans as a percentage of total loans		0.00%	0.01%	0.00%
Consumer loans and overdrafts | 90 Days Past Due
Accrual Loans, Loan Balance
Past Due		$ 885
Past Due	$ 753	$ 896	$ 0	$ 370
Accrued Loans, %
Past due loans, still accruing as a percentage of total loans		0.77%	0.00%	0.30%
Non-Accrual Loans, Loan Balance
Total Non-Accrual Loans		$ 11	$ 19	$ 9
Non-Accrual Loans, %
Total non-accrual loans as a percentage of total loans		0.01%	0.01%	0.01%

Premises and Equipment, Net - S

Premises and Equipment, Net - Schedule (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2019	Dec. 31, 2017
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 195,734		$ 206,154
Less: Accumulated depreciation and amortization	(72,231)		(76,797)
Premises and equipment, net	123,503	$ 123,930	129,357
Land
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	18,307		18,307
Buildings and improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 100,152		93,848
Buildings and improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years
Buildings and improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	30 years
Equipment leased under an operating lease
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	15 years
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 0		19,626
Furniture and equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 21,579		19,832
Furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years
Computer equipment and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 31,225		29,749
Leasehold improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 19,301		18,260
Leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years
Work in progress
Property, Plant and Equipment, Net, by Type [Abstract]
Premises and equipment, gross	$ 5,170		$ 6,532

Premises and Equipment, Net - N

Premises and Equipment, Net - Narrative (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)property	Dec. 31, 2016USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Depreciation and amortization	$ 1,942	$ 2,141	$ 8,543	$ 9,040	$ 9,130
Premises and equipment original cost			$ 800	1,400	1,900
Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, at carrying value				19,100	1,000
Gains on sales of property				$ 11,300	$ 2,000
Disposed of by Sale | New York
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties disposed | property				1
Disposed of by Sale | Florida
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties disposed | property				1

Time Deposits - Narrative (Deta

Time Deposits - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Banking and Thrift [Abstract]
Time deposits, $100,000 or more	$ 1,400	$ 1,400	$ 1,200
Time deposits, $250,000 or more	739	$ 718	$ 624
Time deposits, average interest rate		2.51%	1.26%
Time deposits, including brokered deposits, less than $100,000	$ 589	$ 642	$ 780

Time Deposits Time Deposits - S

Time Deposits Time Deposits - Schedule of Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount
Maturities in year one		$ 1,438,565	$ 1,357,668
Maturities in year two		361,255	331,515
Maturities in year three		168,850	194,175
Maturities in year four		135,265	103,781
Maturities in year five			106,550
2023 and thereafter		283,196	152,745
Total	$ 2,359,132	$ 2,387,131	$ 2,246,434
%
Maturities in year one		60.26%	60.44%
Maturities in year two		15.13%	14.76%
Maturities in year three		7.07%	8.64%
Maturities in year four		5.67%	4.62%
Maturities in year five		11.87%	4.74%
2023 and thereafter			6.80%
Total		100.00%	100.00%

Advances From the Federal Hom_3

Advances From the Federal Home Loan Bank and Other Borrowings (Details) - USD ($)	Dec. 18, 2019	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Maturities in year one		$ 385,000,000	$ 440,000,000	$ 567,000,000
Maturities in year two		265,000,000	306,000,000	155,000,000
Maturities in year three		210,000,000	210,000,000	211,000,000
Maturities in year four		120,000,000	120,000,000	240,000,000
2022 and after			210,000,000
Entity Central Index Key	0001734342
2022 and after		90,000,000	90,000,000	0
Advances from Federal Home Loan Banks		$ 1,070,000,000	1,166,000,000	1,173,000,000
Advances from the FHLB			280,000,000	255,000,000
Stock held of FHLB			57,000,000	57,000,000
Other borrowings			$ 0	$ 12,000,000
3-month LIBOR | Minimum
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Interest Rate 2018		1.80%	0.90%
Interest Rate 2019		1.50%	1.00%
Interest Rate 2020		1.93%	1.50%
Interest Rate 2021		2.48%	1.93%
Interest Rate 2022 and after		2.95%	2.48%
3-month LIBOR | Maximum
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Interest Rate 2018		3.86%	2.03%
Interest Rate 2019		2.74%	3.86%
Interest Rate 2020		3.08%	2.74%
Interest Rate 2021		2.80%	3.08%
Interest Rate 2022 and after		3.23%	3.23%
Floating Rates | Minimum | Maturities in 2019
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Advances from the FHLB, interest rate			2.40%
Floating Rates | Minimum | Maturities in 2018 and 2019
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Advances from the FHLB, interest rate				1.23%
Floating Rates | Maximum | Maturities in 2019
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Advances from the FHLB, interest rate			2.82%
Floating Rates | Maximum | Maturities in 2018 and 2019
Federal Home Loan Bank, Advances by Interest Rate Type, by Maturity [Abstract]
Advances from the FHLB, interest rate				1.71%

Derivative Instruments - Schedu

Derivative Instruments - Schedule of Derivatives (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	$ 4,991	$ 11,491	$ 7,032
Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	4,991	2,388	1,570
Derivatives Designated as Hedging Instruments | Interest Rate Swap Contracts | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	0	9,386	5,462
Derivatives Designated as Hedging Instruments | Interest Rate Swap Contracts | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	0	283	0
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	4,815	1,420	1,375
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	4,815	1,420	1,375
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Customers | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	4,815	1,420	1,375
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Customers | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	0	0	0
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Third Party Broker | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	0	0	0
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Third Party Broker | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	4,815	1,420	1,375
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	176	685	195
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	176	685	195
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Customers | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	0	0	0
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Customers | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	176	685	195
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Third Party Broker | Other Assets
Derivatives, Fair Value [Line Items]
Derivative asset	176	685	195
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Third Party Broker | Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	$ 0	$ 0	$ 0

Derivative Instruments - Narrat

Derivative Instruments - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2019USD ($)instrument	Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)instrument	Dec. 31, 2017USD ($)instrument
Derivatives, Fair Value [Line Items]
Hedge ineffectiveness gain (loss)	$ 0	$ 0	$ 0	$ 0
Derivatives Designated as Hedging Instruments | Federal Home Loan Bank Advances
Derivatives, Fair Value [Line Items]
Federal Home Loan Bank, average floating rate			$ 280,000,000	$ 366,000,000
Derivatives Designated as Hedging Instruments | Federal Home Loan Bank Advances | Maximum
Derivatives, Fair Value [Line Items]
Average remaining maturity			1 year	9 years
Derivatives Designated as Hedging Instruments | Federal Home Loan Bank Advances | Minimum
Derivatives, Fair Value [Line Items]
Average remaining maturity				2 years
Derivatives Designated as Hedging Instruments | Interest Rate Swap Contracts
Derivatives, Fair Value [Line Items]
Number of instruments held | instrument			16	15
Notional amount			$ 280,000,000	$ 255,000,000
Derivatives Designated as Hedging Instruments | Interest Rate Swap Contracts | Maximum
Derivatives, Fair Value [Line Items]
Average remaining maturity			8 years	9 years
Derivatives Designated as Hedging Instruments | Interest Rate Swap Contracts | Minimum
Derivatives, Fair Value [Line Items]
Average remaining maturity			1 year	3 years
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Customers
Derivatives, Fair Value [Line Items]
Number of instruments held | instrument	12		8	1
Notional amount	$ 145,400,000		$ 80,400,000	$ 54,600,000
Average remaining maturity				10 years
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Maximum | Customers
Derivatives, Fair Value [Line Items]
Average remaining maturity			10 years
Derivatives Not Designated as Hedging Instruments | Interest Rate Swap Contracts | Minimum | Customers
Derivatives, Fair Value [Line Items]
Average remaining maturity			5 years
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Customers
Derivatives, Fair Value [Line Items]
Number of instruments held | instrument	16,000		16	7
Notional amount	$ 320,800,000		$ 323,700,000	$ 162,100,000
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Maximum | Customers
Derivatives, Fair Value [Line Items]
Average remaining maturity			5 years	4 years
Derivatives Not Designated as Hedging Instruments | Interest Rate Cap Contracts | Minimum | Customers
Derivatives, Fair Value [Line Items]
Average remaining maturity			1 year	1 year 6 months

Junior Subordinated Debenture_3

Junior Subordinated Debentures Held by Trust Subsidiaries - Narrative (Details) - subsidiary	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Number of trust subsidiaries in which the company owns all the common capital securities	8	8

Junior Subordinated Debenture_4

Junior Subordinated Debentures Held by Trust Subsidiaries - Summary of Junior Subordinated Debentures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2019	Dec. 31, 2017
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	$ 114,080
Principal Amount of Debenture Issued to Trust	118,110	$ 118,110	$ 118,110
Commercebank Capital Trust I | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2028
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 28,068
Annual Rate of Trust Preferred Securities and Debentures	8.90%
Commercebank Statutory Trust II | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2030
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 15,464
Annual Rate of Trust Preferred Securities and Debentures	10.60%
Commercebank Capital Trust III | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2031
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 10,400
Annual Rate of Trust Preferred Securities and Debentures	10.18%
Commercebank Capital Trust VI | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2033
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 9,537
Commercebank Capital Trust VI | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2033 | 3-month LIBOR
Debt Instrument [Line Items]
Variable rate	3.35%
Commercebank Capital Trust VII | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2033
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 8,248
Commercebank Capital Trust VII | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2033 | 3-month LIBOR
Debt Instrument [Line Items]
Variable rate	3.25%
Commercebank Capital Trust VIII | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2034
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 5,155
Commercebank Capital Trust VIII | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2034 | 3-month LIBOR
Debt Instrument [Line Items]
Variable rate	2.85%
Commercebank Capital Trust IX | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2038
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 25,774
Commercebank Capital Trust IX | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2038 | 3-month LIBOR
Debt Instrument [Line Items]
Variable rate	1.75%
Commercebank Capital Trust X | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2036
Debt Instrument [Line Items]
Principal Amount of Debenture Issued to Trust	$ 15,464
Commercebank Capital Trust X | Junior Subordinated Debt | Junior Subordinated Notes, Maturing 2036 | 3-month LIBOR
Debt Instrument [Line Items]
Variable rate	1.78%
Commercebank Capital Trust I
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	$ 26,830
Commercebank Statutory Trust II
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	15,000
Commercebank Capital Trust III
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	10,000
Commercebank Capital Trust VI
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	9,250
Commercebank Capital Trust VII
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	8,000
Commercebank Capital Trust VIII
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	5,000
Commercebank Capital Trust IX
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	25,000
Commercebank Capital Trust X
Debt Instrument [Line Items]
Amount of Trust Preferred Securities Issued by Trust	$ 15,000

Incentive Compensation and Be_2

Incentive Compensation and Benefit Plans (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 21, 2019	Dec. 21, 2018	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 12, 2018
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent of match				100.00%
Employer matching, maximum annual employee salary, matched				5.00%
Employee service requirements for plan participation				3 months
Employee age requirements for plan participation				21 years
Contributions by employer				$ 5	$ 4
Partially compensated plan participants				$ 1.2
Restricted Stock
Defined Contribution Plan Disclosure [Line Items]
Award vesting period		3 years
Restricted Stock Units (RSUs)
Defined Contribution Plan Disclosure [Line Items]
Award vesting period		3 years
Restricted Stock Units (RSUs) | Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)		86,535
Class A common stock | Restricted Stock
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)	1,299	736,839
Grants in period, weighted average grant date fair value (in dollars per share)	$ 13.50	$ 13.45
Share-based compensation expense		$ 0.2	$ 1.5
Unearned deferred compensation expense		$ 9.8	$ 8.3
Unearned deferred compensation expense, weighted average period		2 years	2 years
Award vesting period	3 years
Class A common stock | Restricted Stock Units (RSUs) | Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)		86,535
Shares settled in common shares		57,690
Shares settled in cash upon vesting		28,845
2018 Equity Plan | Class A common stock
Defined Contribution Plan Disclosure [Line Items]
Shares reserved for future issuance (in shares)						3,333,333

Income Taxes - Components (Deta

Income Taxes - Components (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current provision
Federal			$ 7,298	$ 19,194	$ 10,981
State			1,964	1,763	844
Impact of lower rate under the 2017 Tax Act -
Remeasurement of net deferred tax assets, other than balances corresponding to items in AOCI			0	8,470	0
Remeasurement of net deferred tax assets corresponding to items in AOCI			0	1,094	0
Deferred tax expense (benefit)			2,471	3,471	(1,614)
Income tax expense	$ 3,577	$ 1,504	$ 11,733	$ 33,992	$ 10,211

Income Taxes Income Taxes - Nar

Income Taxes Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Change in tax rate, income tax expense	$ 9.6
Net operating loss	143.6	$ 151.9
Deferred tax assets, operating loss carryforwards	$ 6.2	$ 6.6

Income Taxes - Reconciliation (

Income Taxes - Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amount
Tax expense calculated at the statutory federal income tax rate			$ 12,089	$ 26,967	$ 11,827
Remeasurement of net deferred tax assets			0	9,564	0
Non-taxable interest income			(1,507)	(1,643)	(1,132)
Non-taxable BOLI income			(1,223)	(1,910)	(1,547)
Non-deductible Spin-off costs			1,711	0	0
Disallowed interest expense allocable to tax exempt securities and other expenses			627	577	464
State and city income taxes, net of federal income tax benefit			(131)	1,146	549
Other, net			167	(709)	50
Income tax expense	$ 3,577	$ 1,504	$ 11,733	$ 33,992	$ 10,211
%
Tax expense calculated at the statutory federal income tax rate			21.00%	35.00%	35.00%
Remeasurement of net deferred tax assets			0.00%	12.41%	0.00%
Non-taxable interest income			(2.62%)	(2.13%)	(3.35%)
Non-taxable BOLI income			(2.12%)	(2.48%)	(4.58%)
Non-deductible Spin-off costs			2.97%	0.00%	0.00%
Disallowed interest expense allocable to tax exempt securities and other expenses			1.09%	0.75%	1.37%
State and city income taxes, net of federal income tax benefit			(0.23%)	1.49%	1.62%
Other, net			0.29%	(0.92%)	0.16%
Income tax expense	21.49%	13.76%	20.38%	44.12%	30.22%

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Provision for loan losses	$ 13,581	$ 13,372
Net unrealized losses in other comprehensive income	5,878	1,680
Deferred compensation expense	3,489	3,460
Dividend income	605	946
Interest income on nonaccrual loans	341	599
Goodwill amortization	(3,979)	(3,223)
Depreciation and amortization	(3,934)	(3,601)
Other	329	1,350
Net deferred tax assets	$ 16,310	$ 14,583

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (“AOCL”) - Componenets of AOCL (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Before Tax Amount	$ (2,845)	$ (24,042)	$ (7,812)
Tax Effect	696	5,878	1,679
Net of Tax Amount	(2,149)	(18,164)	(6,133)
Unrealized losses on available for sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Before Tax Amount	(11,604)	(33,145)	(13,414)
Tax Effect	2,838	8,104	2,883
Net of Tax Amount	(8,766)	(25,041)	(10,531)
Unrealized gains on interest rate swaps designated as cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Before Tax Amount	8,759	9,103	5,602
Tax Effect	(2,142)	(2,226)	(1,204)
Net of Tax Amount	$ 6,617	$ 6,877	$ 4,398

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss (“AOCL”) - Components of Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Before Tax Amount
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	$ 21,197	$ (14,628)	$ (16,230)	$ 8,769	$ (1,930)
Tax Effect
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	5,182	(4,021)	(4,199)	4,207	(685)
Net of Tax Amount
Reclassification adjustment for net (gains) losses included in net income, Net of Tax Amount	(252)	90	571	833	(1,004)
Other comprehensive (loss) income	16,015	(10,607)	(12,031)	4,562	(1,245)
Unrealized losses on available for sale securities:
Before Tax Amount
Change in fair value arising during the period, Before Tax Amount	21,545	(20,850)	(20,730)	6,875	(5,952)
Reclassification adjustment for net (gains) losses included in net income, Before Tax Amount	(4)	0	999	1,601	(1,556)
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	21,541	(20,850)	(19,731)
Tax Effect
Change in fair value arising during the period, Tax Effect	(5,267)	5,873	5,465	(3,298)	2,113
Reclassification adjustment for net (gains) losses included in net income, Tax Effect	1	0	(244)	(768)	552
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	5,266	(5,873)	(5,221)
Net of Tax Amount
Change in fair value arising during the period, Net of Tax Amount	16,278	(14,977)	(15,265)	3,577	(3,839)
Reclassification adjustment for net (gains) losses included in net income, Net of Tax Amount	(3)	0	755	833	(1,004)
Other comprehensive (loss) income	16,275	(14,977)	(14,510)
Unrealized gains on interest rate swaps designated as cash flow hedges:
Before Tax Amount
Change in fair value arising during the period, Before Tax Amount	(15)	6,101	3,744	293	5,578
Reclassification adjustment for net (gains) losses included in net income, Before Tax Amount	(329)	121	(243)
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(344)	6,222	3,501
Tax Effect
Change in fair value arising during the period, Tax Effect	4	(1,821)	(1,081)	(141)	(1,980)
Reclassification adjustment for net (gains) losses included in net income, Tax Effect	80	(31)	59
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(84)	1,852	1,022
Net of Tax Amount
Change in fair value arising during the period, Net of Tax Amount	(11)	4,280	2,663	$ 152	$ 3,598
Reclassification adjustment for net (gains) losses included in net income, Net of Tax Amount	(249)	90	(184)
Other comprehensive (loss) income	$ (260)	$ 4,370	$ 2,479

Related Party Transactions - Na

Related Party Transactions - Narrative (Details) - USD ($)	Mar. 13, 2018	Feb. 15, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 19, 2018
Related Party Transaction [Line Items]
Available for sale			$ 1,551,591,000		$ 1,586,051,000	$ 1,687,157,000
Loans issued to related parties					5,600,000	4,800,000
Interest income, related party					200,000	200,000
Consideration received on transaction							$ 4,900,000
Sale of stock, gain (loss)							0
Participating mortgage loans					10,000,000	45,000,000
Participating mortgage loans, gain (loss)					0	0
Dividend paid	$ 40,000,000		$ 0	$ 40,000,000	40,000,000	$ 0	0
Dividends, declared (in dollars per share)	$ 0.94
Subsidiary of Common Parent
Related Party Transaction [Line Items]
Payments for license fees					$ 400,000
Subsidiary of Common Parent | Mercantil Bank Holding Corporation
Related Party Transaction [Line Items]
Dividends		$ 19,800,000
Sale of membership interest		8,500,000
Cash		1,000,000
Subsidiary of Common Parent | Mercantil Bank Holding Corporation | Aircraft
Related Party Transaction [Line Items]
Assets		$ 7,500,000
Subsidiary of Common Parent | Loss on sale of securities
Related Party Transaction [Line Items]
Available for sale							11,800,000
Available-for-sale, loss							$ 800,000
Maximum | Mercantil Servicios Financieros, C.A. (MSF)
Related Party Transaction [Line Items]
Percent of shares outstanding owned					5.00%
Maximum | Class B common stock | Mercantil Servicios Financieros, C.A. (MSF)
Related Party Transaction [Line Items]
Percent of shares outstanding owned								5.00%

Related Party Transactions - Ba

Related Party Transactions - Balance Sheet Information (Details) - Subsidiary of Common Parent - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Liabilities [Abstract]
Total due to related parties	$ 14,826	$ 54,035
Demand deposits, noninterest bearing
Liabilities [Abstract]
Due to related parties	9,447	24,879
Demand deposits, interest bearing
Liabilities [Abstract]
Due to related parties	3,721	21,071
Money market
Liabilities [Abstract]
Due to related parties	308	449
Time deposits and accounts payable
Liabilities [Abstract]
Due to related parties	$ 1,350	$ 7,636

Related Party Transactions - Su

Related Party Transactions - Summary of Income and Expenses (Details) - Subsidiary of Common Parent - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income
Revenue from related parties	$ 2,511	$ 3,593	$ 4,387
Expenses
Expenses from transactions with related parties	749	387	1,373
Revenue (expenses) from related parties	1,762	3,206	3,014
Data processing and other services
Income
Revenue from related parties	2,168	1,532	2,328
Rental income from operating lease
Income
Revenue from related parties	248	1,971	1,976
Service charges
Income
Revenue from related parties	95	90	83
Interest expense
Expenses
Expenses from transactions with related parties	126	85	73
Loss on sale of securities
Expenses
Expenses from transactions with related parties	0	0	796
Fees and other expenses
Expenses
Expenses from transactions with related parties	$ 623	$ 302	$ 504

Stockholders_ Equity - Narrativ

Stockholders’ Equity - Narrative (Details)	Mar. 07, 2019USD ($)$ / sharesshares	Feb. 28, 2019shares	Feb. 01, 2019shares	Jan. 23, 2019USD ($)$ / sharesshares	Dec. 28, 2018USD ($)$ / sharesshares	Dec. 21, 2018USD ($)$ / sharesshares	Oct. 23, 2018	Mar. 13, 2018USD ($)$ / shares	Feb. 28, 2019USD ($)	Dec. 31, 2018shares	Mar. 31, 2019USD ($)shares	Mar. 31, 2018USD ($)shares	Dec. 31, 2018USD ($)shares	Dec. 31, 2017USD ($)shares	Dec. 31, 2016USD ($)shares	Dec. 27, 2018shares	Feb. 06, 2018shares	Dec. 31, 2015shares
Class of Stock [Line Items]
Common and preferred stock, shares authorized (in shares)										550,000,000			550,000,000
Stock split, conversion ratio							0.3333
Consideration received on transaction | $															$ 4,900,000
Dividend paid | $								$ 40,000,000			$ 0	$ 40,000,000	$ 40,000,000	$ 0	$ 0
Dividends, declared (in dollars per share) | $ / shares								$ 0.94
2018 Equity Plan | Restricted Stock
Class of Stock [Line Items]
Stock issued during period (in shares)													736,839
Class A
Class of Stock [Line Items]
Common stock, shares issued (in shares)										26,851,832	28,985,996		26,851,832	24,737,470			74,212,408
Common stock, shares outstanding (in shares)										26,851,832	28,985,996		26,851,832	24,737,470
Class A | Common Stock
Class of Stock [Line Items]
Common stock, shares issued (in shares)										26,851,832			26,851,832	24,737,470	24,737,470			24,737,470
Common stock, shares outstanding (in shares)										26,851,832	28,985,996	24,737,470	26,851,832	24,737,470	24,737,470			24,737,470
Stock issued during period (in shares)											2,132,865		1,377,523
Class A | Common Stock | Over-Allotment Option
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)				229,019
Price per share (in dollars per share) | $ / shares				$ 13
Consideration received on transaction | $				$ 3,000,000
Class A | Common Stock | IPO
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)						6,300,000
Price per share (in dollars per share) | $ / shares						$ 13
Class A | Common Stock | Private Placement
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)		1,750,000	153,846
Consideration received on transaction | $									$ 26,700,000
Class A | Common Stock | Private Placement | Subsequent Event
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)		1,750,000	153,846
Consideration received on transaction | $									$ 26,700,000
Class A | Previously Reported
Class of Stock [Line Items]
Common stock, shares issued (in shares)														74,212,408
Common stock, shares outstanding (in shares)														74,212,408
Class B
Class of Stock [Line Items]
Common stock, shares issued (in shares)										17,751,053	17,751,053		17,751,053	17,751,053			53,253,157
Common stock, shares outstanding (in shares)										17,751,053	14,218,596		17,751,053	17,751,053
Common stock, shares outstanding (in shares)										16,330,917			16,330,917
Treasury stock, acquired (in shares)	2,112,321
Treasury stock acquired (in dollars per share) | $ / shares	$ 13.48
Treasury stock acquired | $	$ 28,500,000
Treasury stock (in shares)	2,112,321									1,420,136	3,532,457		1,420,136
Class B | Common Stock
Class of Stock [Line Items]
Common stock, shares issued (in shares)										17,751,053			17,751,053	17,751,053	17,751,053			17,751,053
Common stock, shares outstanding (in shares)										17,751,053	14,218,596	17,751,053	17,751,053	17,751,053	17,751,053			17,751,053
Common stock, shares outstanding (in shares)										16,330,917			16,330,917
Number of shares authorized to be repurchased (in shares)																3,532,457
Treasury stock, acquired (in shares)					1,420,136					1,400,000
Treasury stock acquired (in dollars per share) | $ / shares					$ 12.61
Treasury stock acquired | $					$ 17,900,000
Treasury stock (in shares)					1,420,136
Class B | Common Stock | Subsequent Event
Class of Stock [Line Items]
Treasury stock, acquired (in shares)	2,112,321
Treasury stock acquired (in dollars per share) | $ / shares	$ 13.48
Treasury stock acquired | $	$ 28,500,000
Treasury stock (in shares)	2,112,321
Class B | Previously Reported
Class of Stock [Line Items]
Common stock, shares issued (in shares)														53,253,157
Common stock, shares outstanding (in shares)														53,253,157
Mercantil Servicios Financieros, C.A. (MSF)
Class of Stock [Line Items]
Percent of common stock, outstanding exchanged (in shares)																	100.00%
Mercantil Servicios Financieros, C.A. (MSF) | Class A
Class of Stock [Line Items]
Common stock, exchanged (in shares)																	298,570,328
Mercantil Servicios Financieros, C.A. (MSF) | Class A | Common Stock | IPO
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)						4,922,477
Consideration received on transaction | $						$ 0
Mercantil Servicios Financieros, C.A. (MSF) | Class B
Class of Stock [Line Items]
Common stock, exchanged (in shares)																	215,188,764
Mercantil Bank Holding Corporation | Class A | Common Stock | IPO
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)						1,377,523
Consideration received on transaction | $						$ 17,900,000
Underwriters | Class A | Common Stock | IPO
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)						945,000
Period in force						30 days
Underwriters | Class A | Common Stock | IPO | Subsequent Event
Class of Stock [Line Items]
Number of shares issued in transaction (in shares)				229,019
Price per share (in dollars per share) | $ / shares				$ 13
Consideration received on transaction | $				$ 3,000,000

Stockholders_ Equity - Schedule

Stockholders’ Equity - Schedule of Shares (Details) - $ / shares	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Common stock, shares authorized (in shares)		500,000,000
Preferred stock, shares authorized (in shares)		50,000,000
Preferred stock, par value (in dollars per share)		$ 0.10
Common and preferred stock, shares authorized (in shares)		550,000,000
Class A
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	400,000,000	400,000,000	400,000,000
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10	$ 0.10
Class B
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	100,000,000	100,000,000	100,000,000
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10	$ 0.10

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 1.6	$ 1.4	$ 6	$ 6	$ 6

Commitments and Contingencies_2

Commitments and Contingencies - Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2018USD ($)
Commitments and Contingencies Disclosure [Abstract]
2019	$ 6,281
2020	6,223
2021	5,930
2022	5,386
2023	5,069
Thereafter	43,071
Total future payments, under operating leases	$ 71,960

Commitments and Contingencies_3

Commitments and Contingencies - Summary of Off-Balance Sheet Credit Risk (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Approximate Contract Amount	$ 1,107,910	$ 1,149,156
Commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Approximate Contract Amount	884,142	923,424
Credit card facilities
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Approximate Contract Amount	196,901	198,500
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Approximate Contract Amount	24,278	19,562
Commercial letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Approximate Contract Amount	$ 2,589	$ 7,670

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Securities available for sale
Securities available for sale	$ 1,551,591	$ 1,586,051	$ 1,687,157
Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale	1,551,591	1,586,051	1,687,157
Bank owned life insurance	207,546	206,141	200,318
Derivative instruments	4,991	11,491	7,032
Assets, fair value	1,764,128	1,803,683	1,894,507
Liabilities
Derivative instruments	4,991	2,388	1,570
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale	0	0	0
Bank owned life insurance	0	0	0
Derivative instruments	0	0	0
Assets, fair value	0	0	0
Liabilities
Derivative instruments	0	0	0
Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale	1,551,591	1,586,051	1,687,157
Bank owned life insurance	207,546	206,141	200,318
Derivative instruments	4,991	11,491	7,032
Assets, fair value	1,764,128	1,803,683	1,894,507
Liabilities
Derivative instruments	4,991	2,388	1,570
Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale	0	0	0
Bank owned life insurance	0	0	0
Derivative instruments	0	0	0
Assets, fair value	0	0	0
Liabilities
Derivative instruments	0	0	0
U.S. government sponsored enterprise debt securities
Securities available for sale
Securities available for sale	890,458	820,779	875,666
U.S. government sponsored enterprise debt securities | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale	890,458	820,779	875,666
U.S. government sponsored enterprise debt securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale	0	0	0
U.S. government sponsored enterprise debt securities | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale	890,458	820,779	875,666
U.S. government sponsored enterprise debt securities | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale	0	0	0
Corporate debt securities
Securities available for sale
Securities available for sale	258,342	352,555	313,392
Corporate debt securities | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale	258,342	352,555	313,392
Corporate debt securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale	0	0	0
Corporate debt securities | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale	258,342	352,555	313,392
Corporate debt securities | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale	0	0	0
U.S. government agency debt securities
Securities available for sale
Securities available for sale	215,336	216,985	291,385
U.S. government agency debt securities | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale	215,336	216,985	291,385
U.S. government agency debt securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale	0	0	0
U.S. government agency debt securities | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale	215,336	216,985	291,385
U.S. government agency debt securities | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale	0	0	0
Municipal bonds
Securities available for sale
Securities available for sale	163,988	160,212	180,396
Municipal bonds | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale	163,988	160,212	180,396
Municipal bonds | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale	0	0	0
Municipal bonds | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale	163,988	160,212	180,396
Municipal bonds | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale	0	0	0
Mutual funds
Securities available for sale
Securities available for sale	23,467	23,110	23,617
Mutual funds | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale	23,467	23,110	23,617
Mutual funds | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale	0	0	0
Mutual funds | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale	23,467	23,110	23,617
Mutual funds | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale	0	0	0
Commercial paper
Securities available for sale
Securities available for sale	$ 0	12,410
Commercial paper | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale		12,410
Commercial paper | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale		0
Commercial paper | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale		12,410
Commercial paper | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale		$ 0
U.S. treasury securities
Securities available for sale
Securities available for sale			2,701
U.S. treasury securities | Fair Value, Measurements, Recurring
Securities available for sale
Securities available for sale			2,701
U.S. treasury securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Securities available for sale
Securities available for sale			0
U.S. treasury securities | Fair Value, Measurements, Recurring | Third-Party Models with Observable Market Inputs (Level 2)
Securities available for sale
Securities available for sale			2,701
U.S. treasury securities | Fair Value, Measurements, Recurring | Internal Models with Unobservable Market Inputs (Level 3)
Securities available for sale
Securities available for sale			$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details)	Dec. 31, 2018USD ($)
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets (liabilities) measured at fair value	$ 0

Fair Value Measurements - Ass_2

Fair Value Measurements - Assets Measured at Fair Value on a Nonrecurring Basis (Details) - Fair Value, Measurements, Nonrecurring - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Impairments	$ 0	$ 0
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	9,968	5,611
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	0	0
Significant Other Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 0	$ 0

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Summary of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Carrying Value
Financial assets
Loans	$ 2,792,815	$ 2,850,015	$ 2,682,790
Financial liabilities
Time deposits	1,770,303	1,745,025	1,466,464
Advances from the Federal Home Loan Bank	1,070,000	1,166,000	1,161,000
Junior subordinated debentures	118,110	118,110	118,110
Estimated Fair Value
Financial assets
Loans	2,670,693	2,739,721	2,566,197
Financial liabilities
Time deposits	1,772,212	1,740,752	1,461,908
Advances from the Federal Home Loan Bank	1,074,596	1,167,213	1,164,686
Junior subordinated debentures	$ 114,620	$ 99,450	$ 95,979

Regulatory Matters - Summary of

Regulatory Matters - Summary of Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Dividends		$ 82,600	$ 84,400
Capital conservation buffer		5.50%	5.30%
Capital [Abstract]
Total capital		$ 916,663	$ 926,049
Total capital ratio		13.54%	13.31%
Total minimums capital required for capital adequacy		$ 541,638	$ 556,578
Total minimums capital required for capital adequacy, ratio		8.00%	8.00%
Total capital required to be well capitalized		$ 677,047	$ 695,722
Total capital required to be well capitalized, ratio		10.00%	10.00%
Tier One Risk Based Capital [Abstract]
Tier 1 capital		$ 859,031	$ 852,825
Tier 1 capital ratio		12.69%	12.21%
Tier 1 minimums capital required for capital adequacy		$ 406,228	$ 417,433
Tier 1 minimums capital required for capital adequacy, ratio		6.00%	6.00%
Tier 1 capital required to be well capitalized		$ 541,638	$ 556,578
Tier 1 capital required to be well capitalized, ratio		8.00%	8.00%
Tier One Leverage Capital [Abstract]
Tier 1 leverage capital		$ 859,031	$ 852,825
Tier 1 leverage ratio		10.34%	10.15%
Tier 1 leverage minimums capital required for capital adequacy		$ 332,190	$ 335,647
Tier 1 leverage minimums capital required for capital adequacy, ratio		4.00%	4.00%
Tier 1 leverage capital required to be well capitalized		$ 415,238	$ 419,559
Tier 1 leverage capital required to be well capitalized, ratio		5.00%	5.00%
Common Equity Tier One Capital [Abstract]
Common equity tier 1 (CET1), amount		$ 749,465	$ 753,545
Common equity tier 1 (CET1) , ratio		11.07%	10.68%
Common equity tier 1 (CET1) minimums capital required for capital adequacy		$ 304,671	$ 313,075
Common equity tier 1 (CET1) minimums capital required for capital adequacy, ratio		4.50%	4.50%
Common equity tier 1 (CET1) capital required to be well capitalized		$ 440,080	$ 452,220
Common equity tier 1 (CET1) capital required to be well capitalized, ratio		6.50%	6.50%
Forecast
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital conservation buffer	2.50%
The Bank
Capital [Abstract]
Total capital		$ 883,746	$ 885,855
Total capital ratio		13.05%	12.69%
Total minimums capital required for capital adequacy		$ 541,564	$ 556,446
Total minimums capital required for capital adequacy, ratio		8.00%	8.00%
Total capital required to be well capitalized		$ 676,955	$ 695,557
Total capital required to be well capitalized, ratio		10.00%	10.00%
Tier One Risk Based Capital [Abstract]
Tier 1 capital		$ 826,114	$ 812,631
Tier 1 capital ratio		12.20%	11.68%
Tier 1 minimums capital required for capital adequacy		$ 406,173	$ 417,334
Tier 1 minimums capital required for capital adequacy, ratio		6.00%	6.00%
Tier 1 capital required to be well capitalized		$ 541,564	$ 556,446
Tier 1 capital required to be well capitalized, ratio		8.00%	8.00%
Tier One Leverage Capital [Abstract]
Tier 1 leverage capital		$ 826,114	$ 812,631
Tier 1 leverage ratio		9.96%	9.69%
Tier 1 leverage minimums capital required for capital adequacy		$ 331,829	$ 335,600
Tier 1 leverage minimums capital required for capital adequacy, ratio		4.00%	4.00%
Tier 1 leverage capital required to be well capitalized		$ 414,786	$ 419,500
Tier 1 leverage capital required to be well capitalized, ratio		5.00%	5.00%
Common Equity Tier One Capital [Abstract]
Common equity tier 1 (CET1), amount		$ 826,114	$ 812,631
Common equity tier 1 (CET1) , ratio		12.20%	11.68%
Common equity tier 1 (CET1) minimums capital required for capital adequacy		$ 304,630	$ 313,001
Common equity tier 1 (CET1) minimums capital required for capital adequacy, ratio		4.50%	4.50%
Common equity tier 1 (CET1) capital required to be well capitalized		$ 440,021	$ 452,112
Common equity tier 1 (CET1) capital required to be well capitalized, ratio		6.50%	6.50%

Segment Information (Details)

Segment Information (Details) - segment	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2019
Segment Reporting [Abstract]
Reportable business segments	1	4

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	Jan. 31, 2019	Dec. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income available to common stockholders			$ 13,071	$ 9,429	$ 45,833	$ 43,057	$ 23,579
Basic weighted averages shares outstanding (in shares)			42,755,000	42,489,000	42,487,000	42,489,000	42,489,000
Dilutive effect of shared-based compensation awards (in shares)			159,000	0	0	0	0
Diluted weighted average shares outstanding (in shares)			42,914,000	42,489,000	42,487,000	42,489,000	42,489,000
Basic earnings per common share (in dollars per share)			$ 0.31	$ 0.22	$ 1.08	$ 1.01	$ 0.55
Diluted earnings per common share (in dollars per share)			$ 0.30	$ 0.22	$ 1.08	$ 1.01	$ 0.55
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation				0		0	0
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation			738,138		736,839
Grants in period (in shares)	1,299	736,839

Condensed Unconsolidated Hold_3

Condensed Unconsolidated Holding Companies’ Financial Statements - Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets
Cash and due from banks	$ 26,821	$ 25,756		$ 44,531
Investments in subsidiaries		114,080
Total assets	7,902,355	8,124,347		8,436,767
Liabilities and Stockholders' Equity
Junior subordinated debentures held by trust subsidiaries	118,110	118,110		118,110
Stockholders' equity	778,749	747,418	$ 712,272	753,450	$ 704,737	$ 682,403
Total liabilities and stockholders' equity	$ 7,902,355	8,124,347		8,436,767
Mercantil Bank Holding Corporation | Parent Company | Reportable Legal Entities
Assets
Cash and due from banks		1,891		1,420
Investments in subsidiaries		746,344		752,409
Other assets		1,720		1,798
Total assets		749,955		755,627
Liabilities and Stockholders' Equity
Other liabilities		2,537		2,177
Stockholders' equity		747,418		753,450
Total liabilities and stockholders' equity		749,955		755,627
Mercantil Florida Bancorp, Inc | Subsidiaries | Reportable Legal Entities
Assets
Cash and due from banks		32,922		39,089
Investments in subsidiaries		822,940		821,982
Other assets		9,640		9,775
Total assets		865,502		870,846
Liabilities and Stockholders' Equity
Junior subordinated debentures held by trust subsidiaries		118,110		118,110
Other liabilities		1,048		979
Stockholders' equity		746,344		751,757
Total liabilities and stockholders' equity		$ 865,502		$ 870,846

Condensed Unconsolidated Hold_4

Condensed Unconsolidated Holding Companies’ Financial Statements - Income Statement Information (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income
Interest	$ 80,307	$ 71,931	$ 309,358	$ 273,320	$ 238,827
Expenses
Employee compensation and benefit	33,437	34,041	141,801	131,800	129,681
Interest Expense	24,870	19,298	90,319	63,610	46,894
Provision for (reversal of) loan losses	0	0	375	(3,490)	22,110
Other expenses	4,661	4,773	10,365	15,567	13,664
Net income before income tax	16,648	10,933	57,566	77,049	33,790
Income tax (expense) benefit	(3,577)	(1,504)	(11,733)	(33,992)	(10,211)
Net income	$ 13,071	$ 9,429	45,833	43,057	23,579
Mercantil Bank Holding Corporation | Parent Company | Reportable Legal Entities
Income
Interest			9	3	2
Equity in earnings of subsidiary			53,939	45,008	23,996
Total income			53,948	45,011	23,998
Expenses
Employee compensation and benefit			0	350	350
Other expenses			8,018	2,539	250
Total expense			8,018	2,889	600
Net income before income tax			45,930	42,122	23,398
Income tax (expense) benefit			(97)	935	181
Net income			45,833	43,057	23,579
Mercantil Florida Bancorp, Inc | Subsidiaries | Reportable Legal Entities
Income
Interest			182	85	33
Equity in earnings of subsidiary			60,609	50,982	31,282
Total income			60,791	51,067	31,315
Expenses
Interest Expense			8,086	7,456	7,129
Provision for (reversal of) loan losses			0	0	1,838
Other expenses			414	1,310	1,361
Total expense			8,500	8,766	10,328
Net income before income tax			52,291	42,301	20,987
Income tax (expense) benefit			1,661	2,726	3,031
Net income			$ 53,952	$ 45,027	$ 24,018

Condensed Unconsolidated Hold_5

Condensed Unconsolidated Holding Companies’ Financial Statements - Cash Flow Information (Details) - USD ($) $ in Thousands	Mar. 13, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income		$ 13,071	$ 9,429	$ 45,833	$ 43,057	$ 23,579
Net cash provided by operating activities		12,581	13,641	62,161	73,282	75,268
Cash flows from investing activities
Net cash provided by (used in) investing activities		230,590	121,339	206,509	7,567	(322,228)
Dividend paid	$ (40,000)	0	(40,000)	(40,000)	0	0
Proceeds from common stock issued - Class A		29,218	0	17,908	0	0
Repurchase of common stock - Class B		(28,465)	0	(17,908)	0	0
Net cash (used in) provided by financing activities		(239,192)	(22,768)	(336,405)	(62,393)	243,667
Cash and cash equivalents
Beginning of period		85,710	153,445	153,445
End of period		89,689		85,710	153,445
Mercantil Bank Holding Corporation | Parent Company | Reportable Legal Entities
Cash flows from operating activities
Net income				45,833	43,057	23,579
Adjustments to reconcile net income to net cash used in operating activities - Equity in earnings of subsidiaries				(53,939)	(45,008)	(23,996)
Net change in other assets and liabilities				438	1,337	(2)
Net cash provided by operating activities				(7,668)	(614)	(419)
Cash flows from investing activities
Cash received upon Voting Trust termination				639	0	0
Dividends received from subsidiary				47,500	700	400
Net cash provided by (used in) investing activities				48,139	700	400
Dividend paid				(40,000)	0	0
Proceeds from common stock issued - Class A				17,908	0	0
Repurchase of common stock - Class B				(17,908)	0	0
Net cash (used in) provided by financing activities				(40,000)	0	0
Net increase (decrease) in cash and cash equivalents				471	86	(19)
Cash and cash equivalents
Beginning of period		1,891	1,420	1,420	1,334	1,353
End of period				1,891	1,420	1,334
Mercantil Florida Bancorp, Inc | Subsidiaries | Reportable Legal Entities
Cash flows from operating activities
Net income				53,952	45,027	24,018
Adjustments to reconcile net income to net cash used in operating activities - Equity in earnings of subsidiaries				(60,609)	(50,982)	(31,282)
Net change in other assets and liabilities				490	(4)	(35)
Net cash provided by operating activities				(6,167)	(5,959)	(7,299)
Cash flows from investing activities
Dividends received from subsidiary				47,500	6,000	6,000
Dividends paid				(47,500)	(700)	(400)
Net cash provided by (used in) investing activities				0	5,300	5,600
Net increase (decrease) in cash and cash equivalents				(6,167)	(659)	(1,699)
Cash and cash equivalents
Beginning of period		$ 32,922	$ 39,089	39,089	39,748	41,447
End of period				$ 32,922	$ 39,089	$ 39,748

Uncategorized Items - mbhc-2019

Label	Element	Value
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	$ 265,657,000
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	$ 89,689,000