Business Combinations - Pro-Forma Financial Information And Actual Results of Acquisition (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares
Business Combinations [Abstract]
Net interest income \| $	$ 163,968
Net income available to common shareholders \| $	$ 65,178
EPS - basic \| $ / shares	$ 0.50
EPS - diluted \| $ / shares	$ 0.50

Business acquisition pro forma interest income net.

No definition available.

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- Definition

Business acquisition pro forma net income loss available to common stockholders.

+ References

No definition available.

+ Details

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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- References

No definition available.

+ Details

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