Parent Company Only Financial Statements Parent Company Only Financial Statements (Tables)

12 Months Ended

Dec. 31, 2017

Condensed Financial Information of Parent Company Only Disclosure [Abstract]

Condensed Balance Sheet [Table Text Block]

Balance Sheets

(In thousands)

	December 31,
	2017			2016
Assets
Cash and cash equivalents	$	205,876		$	163,418
Available for sale securities	16,185			19,234
Investment in bank subsidiaries	3,255,912			3,067,595
Investment in non-bank subsidiaries	170,966			177,068
Other assets	4,065			4,865
Total assets	$	3,653,004		$	3,432,180
Liabilities and Shareholders’ Equity
Liabilities:
Other liabilities	$	12,960		$	5,469
Other borrowings – Trust preferred debt	—			7,217
Subordinated debentures	144,677			144,640
Total liabilities	157,637			157,326
Shareholders’ equity:
Common stock	4			4
Capital surplus	1,035,895			1,006,535
Retained earnings	3,048,487			2,823,334
Treasury stock	(552,845		)	(544,052		)
Accumulated other comprehensive loss	(36,174		)	(10,967		)
Total shareholders’ equity	3,495,367			3,274,854
Total liabilities and shareholders’ equity	$	3,653,004		$	3,432,180

Condensed Income Statement [Table Text Block]

Statements of Earnings

(In thousands)

	Year Ended December 31,
	2017			2016			2015
Dividends, interest and fees received from bank subsidiaries	$	150,149		$	15,237		$	150,308
Dividends, interest and fees received from non-bank subsidiaries	17,500			25,923			—
Other revenue	936			1,612			1,279
Total revenue	168,585			42,772			151,587
Interest expense	8,239			4,182			131
Other operating expense	2,014			1,978			2,242
Total expense	10,253			6,160			2,373
Income before taxes and equity in undistributed income of subsidiaries	158,332			36,612			149,214
Federal and state income taxes	(4,305		)	(1,920		)	(375		)
Income before equity in undistributed income of subsidiaries	162,637			38,532			149,589
Equity in undistributed income of bank subsidiaries	181,552			216,120			134,045
Equity in undistributed income of non-bank subsidiaries	(9,545		)	(21,984		)	4,931
Net income attributable to BOK Financial Corp. shareholders	$	334,644		$	232,668		$	288,565

Condensed Cash Flow Statement [Table Text Block]

Statements of Cash Flows

(In thousands)

	Year Ended December 31,
	2017			2016			2015
Cash Flows From Operating Activities:
Net income	$	334,644		$	232,668		$	288,565
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed income of bank subsidiaries	(181,552		)	(216,120		)	(134,045		)
Equity in undistributed income of non-bank subsidiaries	9,545			21,984			(4,931		)
Change in other assets	12			(2,933		)	49
Change in other liabilities	7,457			(1,285		)	(2,818		)
Net cash provided by operating activities	170,106			34,314			146,820
Cash Flows From Investing Activities:
Proceeds from sales of available for sale securities	3,000			1,632			4,760
Investment in subsidiaries	(4,355		)	(26,000		)	(41,969		)
Acquisitions, net of cash acquired	—			(105,520		)	—
Net cash used in investing activities	(1,355		)	(129,888		)	(37,209		)
Cash Flows From Financing Activities:
Net change in other borrowings	(7,217		)	—			—
Issuance of subordinated debentures, net of issuance costs	—			144,615			—
Issuance of common and treasury stock, net	4,368			12,455			6,711
Dividends paid	(116,041		)	(113,455		)	(115,281		)
Repurchase of common stock	(7,403		)	(66,792		)	(229,540		)
Net cash used in financing activities	(126,293		)	(23,177		)	(338,110		)
Net increase (decrease) in cash and cash equivalents	42,458			(118,751		)	(228,499		)
Cash and cash equivalents at beginning of period	163,418			282,169			510,668
Cash and cash equivalents at end of period	$	205,876		$	163,418		$	282,169
Cash paid for interest	$	6,211		$	4,127		$	131