Offsetting Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2014

Offsetting [Abstract]

Offsetting Assets and Liabilities [Table Text Block]

The composition of offsetting derivative instruments, financial assets, and financial liabilities was as follows.

	Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset in the Consolidated Balance Sheet		Net Amounts of Assets/(Liabilities) Presented in the Consolidated Balance Sheet
									Gross Amounts Not Offset in the Consolidated Balance Sheet
December 31, 2014 ($ in millions)									Financial Instruments			Collateral (a)			Net Amount
Assets
Derivative assets in net asset positions	$	216		$	—	$	216		$	(60	)	$	(68	)	$	88
Derivative assets in net liability positions	47			—		47			(47		)	—			—
Total assets (b)	$	263		$	—	$	263		$	(107	)	$	(68	)	$	88
Liabilities
Derivative liabilities in net liability positions	$	(188	)	$	—	$	(188	)	$	47		$	54		$	(87	)
Derivative liabilities in net asset positions	(60		)	—		(60		)	60			—			—
Derivative liabilities with no offsetting arrangements	(4		)	—		(4		)	—			—			(4		)
Total derivative liabilities (b)	(252		)	—		(252		)	107			54			(91		)
Securities sold under agreements to repurchase (c)	(774		)	—		(774		)	—			774			—
Total liabilities	$	(1,026	)	$	—	$	(1,026	)	$	107		$	828		$	(91	)

(a) Financial collateral received/pledged shown as a balance based on the sum of all net asset and liability positions between Ally and each individual derivative counterparty.

(b) For additional information on derivative instruments and hedging activities, refer to Note 22.

(c) For additional information on securities sold under agreements to repurchase, refer to Note 15.

	Gross Amounts of Recognized Assets/(Liabilities)			Gross Amounts Offset in the Consolidated Balance Sheet		Net Amounts of Assets/(Liabilities) Presented in the Consolidated Balance Sheet
									Gross Amounts Not Offset in the Consolidated Balance Sheet
December 31, 2013 ($ in millions)									Financial Instruments			Collateral (a)			Net Amount
Assets
Derivative assets in net asset positions	$	319		$	—	$	319		$	(65	)	$	(120	)	$	134
Derivative assets in net liability positions	43			—		43			(43		)	—			—
Total assets (b)	$	362		$	—	$	362		$	(108	)	$	(120	)	$	134
Liabilities
Derivative liabilities in net liability positions	$	(252	)	$	—	$	(252	)	$	43		$	137		$	(72	)
Derivative liabilities in net asset positions	(65		)	—		(65		)	65			—			—
Total derivative liabilities (b)	(317		)	—		(317		)	108			137			(72		)
Securities sold under agreements to repurchase (c)	(1,500		)	—		(1,500		)	—			1,500			—
Total liabilities	$	(1,817	)	$	—	$	(1,817	)	$	108		$	1,637		$	(72	)

(a) Financial collateral received/pledged shown as a balance based on the sum of all net asset and liability positions between Ally and each individual derivative counterparty.

(b) For additional information on derivative instruments and hedging activities, refer to Note 22.

(c) For additional information on securities sold under agreements to repurchase, refer to Note 15.