Fair Value Measurements, Call Option FV Assumption Table (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013 basispoints		Sep. 30, 2013 basispoints		Sep. 30, 2012
Fair Value Disclosures [Abstract]
The Company’s stock price at September 30, 2013	$ 71.25		$ 71.25
Quarterly dividend yield (per share) upon purchase of the Call Option	$ 0.24	[1]
Risk-free interest rate			0.21%	[2]
Credit spread (basis points)	228	[3]	228	[3]
Expected volatility rate			17.00%	[4]
Cash dividends paid per share	$ 0.30		$ 0.90		$ 0.75
Constant Maturity Treasury rate	1.5		1.5

[1] The quarterly dividend in the third quarter of 2013 was $0.30 per share, but the model assumes a $0.24 per share quarterly dividend as was paid at the inception of the Call Options. Quarterly dividends in excess of $0.24 per share do not affect the Call Options’ value due to anti-dilution adjustments.

[2] The risk-free rate was based on the 1.5-year Constant Maturity Treasury rate on September 30, 2013.

[3] The credit spread is based on the Company’s long-term credit rating of BB- issued by Standard & Poor’s and a senior unsecured credit rating of Ba3 issued by Moody’s.

[4] The volatility rate was based on both observed volatility, which is based on the Company’s historical stock price, and implied volatility from the Company’s traded options. Such volatility was further adjusted to take into consideration market participant risk tolerance.