11. Fair Value measurements (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Finance Receivables Measured at Fair Value:
Balance at beginning of period	$ 102,366	$ 0	$ 160,253	$ 0
Acquisitions	0	199,554	0	199,554
Payments on finance receivables at fair value	(22,449)	(6,886)	(86,556)	(6,886)
Charge-offs on finance receivables at fair value	(1,259)	0	(5,309)	0
Discount accretion	1,870	(50)	7,272	(50)
Mark to fair value	(3,044)	0	1,824	0
Balance at end of period	77,484	192,618	77,484	192,618
Debt Secured by Finance Receivables Measured at Fair Value:
Balance at beginning of period	104,662	0	166,828	0
New issuances	0	196,473	0	196,473
Principal payments on debt at fair value	(26,902)	0	(97,703)	0
Premium accretion	1,687	240	5,552	240
Mark to fair value	(2,817)	0	1,953	0
Balance at end of period	76,630	196,713	76,630	196,713
Reduction for principal payments collected and payable	(7,002)	(8,313)	(7,002)	(8,313)
Adjusted balance at end of period	$ 69,628	$ 188,400	$ 69,628	$ 188,400