Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income attributable to TCF Financial Corporation	$ 304,358	$ 268,637	$ 212,124
Other comprehensive income (loss), net of tax:
Net unrealized gains (losses) on debt securities available for sale and interest-only strips	(11,669)	16,454	(18,894)
Net unrealized gains (losses) on net investment hedges	10,450	(2,746)	(756)
Foreign currency translation adjustment	(13,368)	4,921	1,300
Recognized postretirement prior service cost	(34)	(29)	(29)
Total other comprehensive income (loss), net of tax	(14,621)	18,600	(18,379)
Comprehensive income	$ 289,737	$ 287,237	$ 193,745

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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