Equity (Tables)

12 Months Ended

Dec. 31, 2012

Equity [Abstract]

Schedule of Stockholders Equity [Table Text Block]

Our common stock has a par value of $0.01 and there are 2,021,384 shares authorized for issuance. Our common stock is not registered with the Securities and Exchange Commission, and there is no established trading market for the shares. Treasury holds 73.78% of Ally common stock. The following table presents changes in the number of shares issued and outstanding.

(in shares)	2012	2011	2010
Common stock
January 1,	1,330,970	1,330,970	799,120
New issuances
Conversion of Series F-2 Preferred Stock (a)	—	—	531,850
December 31,	1,330,970	1,330,970	1,330,970

(a) On December 30, 2010, 110,000,000 shares of Series F-2 Preferred Stock owned by Treasury were converted into 531,850 shares of Ally common stock.

Schedule of Stock by Class [Table Text Block]

The following table summarizes information about our Series F-2, Series A, and Series G preferred stock.

December 31,	2012			2011
Mandatorily convertible preferred stock held by U.S. Department of Treasury
Series F-2 preferred stock (a)
Carrying value ($ in millions)	$	5,685		$	5,685
Par value (per share)	0.01			0.01
Liquidation preference (per share)	50			50
Number of shares authorized	228,750,000			228,750,000
Number of shares issued and outstanding	118,750,000			118,750,000
Dividend/coupon	9		%	9		%
Redemption/call feature	Perpetual (b)			Perpetual (b)
Preferred stock
Series A preferred stock
Carrying value ($ in millions)	$	1,021		$	1,021
Par value (per share)	0.01			0.01
Liquidation preference (per share)	25			25
Number of shares authorized	160,870,560			160,870,560
Number of shares issued and outstanding	40,870,560			40,870,560
Dividend/coupon
Prior to May 15, 2016	8.5		%	8.5		%
On and after May 15, 2016	three month LIBOR + 6.243%			three month LIBOR + 6.243%
Redemption/call feature	Perpetual (c)			Perpetual (c)
Series G preferred stock (d)
Carrying value ($ in millions)	$	234		$	234
Par value (per share)	0.01			0.01
Liquidation preference (per share)	1,000			1,000
Number of shares authorized	2,576,601			2,576,601
Number of shares issued and outstanding	2,576,601			2,576,601
Dividend/coupon	7		%	7		%
Redemption/call feature	Perpetual (e)			Perpetual (e)

(a) Mandatorily convertible to common equity on December 30, 2016.

(b) Convertible prior to mandatory conversion date with consent of Treasury.

(c) Nonredeemable prior to May 15, 2016.

(d) Pursuant to a registration rights agreement, we are required to maintain an effective shelf registration statement. In the event we fail to meet this obligation, we may be required to pay additional interest to the holders of the Series G Preferred Stock.

(e) Redeemable beginning at December 31, 2011.