Fair Value Measurements, Call Option FV Assumption Table (Details) (USD $)	3 Months Ended
	Mar. 31, 2014 basispoints		Mar. 31, 2013
Fair Value Disclosures [Abstract]
The Company’s stock price	$ 71.42
Risk-free interest rate	0.13%	[1]
Credit spread (basis points)	154	[2]
Expected volatility rate	17.00%	[3]
Cash dividends paid per share	$ 0.35		$ 0.30
Constant Maturity Treasury rate	1 year

[1] The risk-free rate was based on the one-year Constant Maturity Treasury rate on March 31, 2014.

[2] 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.

[3] 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.