Other Assets (Other Assets - Additional Information) (Detail)		Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Dec. 31, 2015	Jun. 30, 2014	[1]	Sep. 30, 2013	[1]	Jun. 30, 2013	[1]	Dec. 31, 2012	[1]	Mar. 31, 2012	Jun. 30, 2009
Other assets
Percentage of Vantiv Holding, LLC sold to Advent for cash and warrants																51.00%
Percentage of ownership under the equity method of accounting	[1]		3.30%	4.90%	8.60%
Worldpay Holding, LLC
Other assets
Percentage of Vantiv Holding, LLC sold to Advent for cash and warrants																51.00%
Percentage of ownership under the equity method of accounting		3.30%				18.30%	22.80%		25.10%		27.70%		33.10%		39.00%	49.00%

[1] (a) The Bancorp’s remaining investment in Worldpay Holding, LLC of $ 420 as of December 31, 2018 was accounted for as an equity method investment in the Bancorp’s Consolidated Financial Statements.