Shareholders' Equity, Dividends Restrictions and Other Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2017

Regulatory Capital Requirements [Abstract]

Schedule of Compliance with Regulatory Capital Requirements

Following is an analysis of capital ratios under Basel III guidelines for BancShares and FCB as of December 31, 2017 and 2016:

	December 31, 2017						December 31, 2016
(Dollars in thousands)	Amount		Ratio		Requirements to be well-capitalized		Amount		Ratio		Requirements to be well-capitalized
BancShares
Tier 1 risk-based capital	$	3,287,364	12.88	%	8.00	%	$	2,995,557	12.42	%	8.00	%
Common equity Tier 1	3,287,364		12.88		6.50		2,995,557		12.42		6.50
Total risk-based capital	3,626,789		14.21		10.00		3,339,986		13.85		10.00
Leverage capital	3,287,364		9.47		5.00		2,995,557		9.05		5.00
FCB
Tier 1 risk-based capital	3,189,709		12.54		8.00		2,942,829		12.25		8.00
Common equity Tier 1	3,189,709		12.54		6.50		2,942,829		12.25		6.50
Total risk-based capital	3,422,634		13.46		10.00		3,172,757		13.21		10.00
Leverage capital	3,189,709		9.22		5.00		2,942,829		8.94		5.00